The #2 thing, I do it too. And I don't mean "in case something else comes along", because my social life right now is miniscule, and the chance of anything, let alone something better, coming up is very very small.
For whatever reason, I just have a problem scheduling myself too far out (other than vacations, it seems). I worry that I've forgotten something, and the chance of DH being gone on a work trip is high nowadays. If it's more than a month out, DS's classes at the Y might be different and that might get in the way. etc etc. But even when I was single and fancy free it was hard to think that far out.
Now...since I've been doing this for a long time, even before I had others dictating my schedule, I know it's something I need to change. Had that hit me in the face pretty hard last weekend. A friend's sister let me know 3 months ago about a big party she was having for her sister and husband's birthdays. I didn't even look at the evite until it was maybe a month out. RSVPd the NIGHT before they needed the RSVPs.

Didn't even look into how to get there until the day before, and we got there very late. Late meant 5pm, but it was a drive, a ferry trip, and more of a drive, and the second part was on 2 lane, fast roads in the pitch black that rural coastal WA can be. We didn't plan to stay the night, and so we got to drive back home (2 hours plus an hour wait for the ferry because I didn't look up the info and we got there 5 minutes after the ferry left) starting at 11pm in the even more pitch black.
I *should have* just RSVPd and made plans, instead of letting myself float along thinking it would all work out without my putting any effort into it. They were adamant about NO GIFTS, and I believed them (they have everything they want and need), and then...realized I should have gotten them cards b/c everyone else had.
So I do have to change this. But I do NOT mean that I'm waiting for something else or better to come along...
I will enjoy the event once I'm there but I don't look forward to going, if you know what I mean.
I totally get what you mean.

Um ok. I was answering the question, not really a peave for me.
Sometimes what someone said will strike a chord with someone else, and they'll go off of that, but still talking to someone else.
She might appreciate it. Otherwise, people sometimes suspect you're waiting to see if you get a better offer.
To me, they are the same statement. In fact, to me, the statement *you* came up with is actually *more* potentially offensive.
I guess they have no understanding of little things like needing to know how many people you are buying food for or how many places to set at the table(s).
What am I supposed to do with that little piece of information?
I'm a stepkid.

If they are young, then no, they likely do NOT have any idea of how much work it took. I watched my mom working in the kitchen, and still have no real idea of how to prepare for a party. I'll get halfway into party-planning and I'll realize that I'm woefully unprepared. I've been late to two of my OWN parties b/c I had to go out at the last minute to get something. The second time, I stopped giving parties. Anyway, if they've never created a Thanksgiving, they probably do NOT know.
I'd talk to the stepdaughter to get the friend's info to talk to him/her. Gluten free is tricky. I wouldn't know a thing other than "no wheat". And I'm vegetarian sometimes vegan, and we have to avoid all things corn syrup-related. So we are tricky dining folks, but gluten-free? Forget about it, no clue.
Therefore, you need to talk to her. What if she's gluten-free AND vegetarian? No turkey, so then what? And there are different levels of it, it seems, with some people more sensitive than others. etc. So talk to her.
That touches on my pet peeve. When I am so excited to take a bubble bath and one of my daughters has used up all of my bubbles!
Hide your bubbles!
It's not like gluten-free is hard.
Maybe to you. For me...it's mystifying.