I agree that how we (the collective "we") view tipping depends on where we live in the world, and maybe even where we live in the US.
I grew up near NYC and now live near Boston; both places it's customary to tip almost everyone. LOL
I grew up being taught to tip (when traveling):
**Airline baggage handlers ("JFK"

"Honolulu!!!"

[Seinfeld joke! lol])
**Hotel baggage handlers
**Valet (if you have or rent a car and have it parked for you)
**Restaurants on land, of course
**Hotel room service delivery person (percentage of cost of meal, if delivery fee not included in total)
**Cruise ship room service ($2-$3 per meal ordered; last cruise I had a lot of "free" Gatorade and gingerale delivered, and I tipped anyway, even though there was no slip to sign).
The only people who would absolutely NOT accept a tip no matter how hard I tried to give them (to several different CMs) were the Guest Services desk CMs who literally RAN the Pedialyte freezer pops up to me when I called to request them. They were awesome, and even brought us a nice gift basket on our last night.

I specifically mentioned these CMs on the form before we debarked the ship, and also in an email once we were home.
There was one lunch that we had on the last day when I was out of quarantine. We went to Lumiere's. I had no appetite and was still nauseous so I had soup and crackers. For dessert my DH ordered something, and then I asked the CM that was serving us if they had any sorbet. I was still feeling very dehydrated and I figured some sorbet would be good. He said they had mango sorbet. I/m not a fan of mango so I told him "Ok thank you, I was hoping you had lemon sorbet". He paused for a moment and asked me if I was feeling ok (I guess he realized that I only had soup and crackers thus far), so I told him I'd been really sick and quarantined. He replied "Oh I understand, I'm sorry that we only have mango sor...... *he stops talking for 2 seconds*... I will be right back! I will get you lemon sorbet from Palo!"
I was SO thankful, nobody will ever understand what this CMs action meant to me in that moment!!!




He was back in 10 minutes with a dish of Palo's lemon sorbet (which I've loved for years!) PLUS he had a "to-go" container of the sorbet for me to take back to my cabin.
I gave him an excellent review before we left the ship, and I also wrote to
DCL to tell them what his decision that day meant to me.
This awesome CMs name is Jimmey. He was fairly young but he was not only a great server, he displayed great empathy that day.
As always, the above are my own humble opinions, and personal experiences.
Oh, almost forgot to add: My DH gave him a nice tip for going above and beyond what we consider the usual lunch service.