Some people on these boards are like my old next door neighbor - whatever they do is the prefect way, and whatever anyone else does that is different, is the Worst. Thing. EVER.
Geesh....it's a STROLLER. Nobodys vacation will be ruined by you having a stroller on the off chance your kids will want to ride in it for a bit. Judgey (my new favorite made-up word!) people will always judge...of course your DD can walk...you even said she is a cheerleader. As a mom of a 9 year old cheerleader myself, I completely understand the stamina that sport takes - 2 hour practices 3-5 days a week at minimum, usually more, and full of tumbling, conditioning, and strength training (they HAVE to be strong enough to lift the fliers!!), plus dance choreography. She is in better shape during cheer season than any other time of the year!!
OP - my DS will be 8 next month, and he was exhausted in November on our trip by the middle of the 2nd day. We went literally 4 days after he played in his tackle football Superbowl game at the end of our 5 month football season, where he practiced 2 hours/day 3-5 days a week and played in weekend games. Just like DD and cheer, DS8 was in peak physical shape, and was still tired by the 2nd day.
Don't worry about what everyone says - bring it if you want to.
(The other thing that I find hilarious in the threads is all of the people who claim their kid would NEVER hop into a stroller...hahaha....I must have freaks for kids then, because mine would love to hitch a ride at the end of the day. Hmmm...for that matter, so would I!)