Excuse me, isn't this stuff common sense?
I would avoid trying to serve an assertion by referring to it as "common" sense. The vast majority of times I see the term "common" sense used, I see it used to defend an assertion that one's own personal beliefs and values are concepts that "are" (or at least "should be") adhered to be everyone, instead of just those folks who choose to subscribe to those personal beliefs. In a way, assertions of what is "common" sense are nothing more than assertions that "everyone should agree with me" and that people who disagree are thereby, in some way, morally or ethically defective. This belies one of the few true concepts that qualify as "common" sense: The Golden Rule, i.e., the sense that we should each treat each other as we would have ourselves be treated. There are very few, if any, people who would deny the logic of The Golden Rule. However, one inescapable realization derived from The Golden Rule is that if you don't want someone else's beliefs and values imposed on you, then you must never seek to impose your own beliefs and values onto others.
"Common sense" is not the only term that is abused in this manner. All its synonyms and derivatives are similarly abused, including etiquette.
We
can talk about which aspects of the set of rules set forth in the article we personally agree with. We can even assert that some of them
are "common" sense,
but if they are common sense then there wouldn't be any significant disagreement about them, and as such there would be not much interest in discussing them. If there is significant disagreement, you can readily conclude that the element of etiquette is
not common sense, but rather a rule that perhaps many people like, and perhaps even like to impose on others, in violation, perhaps, of the Golden Rule.
Who would stick gum in a magazine for the next person to find?
I think you can make a good argument for that one being truly "common" sense. I cannot imagine anyone, not even the gum-chewer, who would say that doing that is reasonable conduct.
Except there might be a good explanation. Very often in the past (though not so much anymore) the announcement pointing you towards the magazine has indicated that it is there for you to take with you if you wish. The airlines actually had, as part of the routine overnight cleaning of the aircraft, a step whereby the magazines in the seat pockets were replenished. This may be a surprise to some folks, but that was the original intention of the magazine, and they even hoped that some folks would like the magazine so much that they'd actually subscribe. Many of us older folks remember those days, and some still perhaps think of the magazine as their own, and so having used it, they perhaps intended to discard it with their used gum but forgot. Wasteful conduct? Yes. However, given their assumptions about the magazine begin intended for their own personal use, something which, to this day, we cannot say that the airlines have ever revoked, not necessarily evil conduct.
And this reminds me of something that comes up quite often in the mud-slinging threads regarding men giving up their seat to women, on the Disney Transportation buses -- the very critical and valid point is often made that you cannot, just by looking, understand what physical limitations a seated man may have, and so judging him poorly because he doesn't give up his seat is
doubly wrong, first, because you are imposing your own beliefs and values on him, and second, you might be wrong about his physical condition.
I've never understood why the person sitting in row 26 has to put his carryon in the overhead above row 7.
I don't bring carry-ons on-board anymore that would go into the overhead compartment, for just this reason -- I check all much larger pieces and bring fewer bags and fewer clothes if necessary. However, to help you understand this personal situation, quite often when you get back to row 26, it is possible that all the overhead compartments are already full. Generally, savvy travelers know to look down the aircraft toward your row, and aim to put your larger baggage in the last overhead
before your row, for which you can see that it has enough room. Sometimes (especially when a lot of families pre-board), you really perhaps cannot see a suitable overhead compartment anywhere between row 7 and row 26, since aircraft are loaded from back to front. What is very clear (and the airlines say this repeatedly), but what a lot of folks, when it convenient for them, choose to ignore, is that the overhead are shared space... shared with everyone in your compartment, not just your row. There are rows that have no overheads, and rows for which the overheads are used for on-board equipment or crew bags. The sense of entitlement regarding "your" overhead is actually a reflection of poor etiquette, as defined by the rules we all agree to when we purchase airline tickets. So here you see an example of where something that you thought was "wrong" could actually have been okay, and the assertion that it was "wrong" was actually wrong, itself.
This problem is only going to get worse as more airlines charge a fee to check your suitcases.
I really think that the right answer to this is to charge for every piece you carry, and you have to declare before your flight exactly what pieces you'll carry-on. I would love to see FedEx and UPS open up offices in the lobbies of every sizable airport in the country, and the rules and processes changes to effectively feed lots of business to FedEx and UPS, carrying items that used to be carried aboard flights. That's just my personal preference, though. I wouldn't consider it proper etiquette or "common" sense.
Who would stick gum in a magazine for the next person to find? I've never understood why the person sitting in row 26 has to put his carryon in the overhead above row 7.
), but if you want to carry everything but the kitchen sink (cases of water and air mattresses) then don't expect others to pay the same as you. Let's say you have someone that carries a heavy 62" checked bag, a 23" carryon that is so heavy she must have help and it must be squished into the over head bin and then prised out of there when she gets to her destination, plus she has a huge tote that must also go in the overhead bin, because it's too big to go under her feet, then she also tries to bring on a huge WDW shopping bag that must also be squeezed into the overhead. In other words she has a big heavy bag underneath the plane, plus she's taking up three slots in the overhead with her huge carry on, heavy tote, and big shopping bag. Then sitting next to her you have a traveler carrying only a light 20" carry on and a small tote that easily fits under their seat. Why should the second lady pay the same amount as the first? She is not taking up near the space or taking near the time loading that the first lady is, plus her bags weigh alot less. Sorry, but I have no problem with the current bag fees and agree with a previous poster that airlines should start charging a fee for anything that has to go in the overheads,as well as underneath the plane. People would pack lighter, planes would weigh less, so use less fuel, and planes would load alot faster. 
