How come some Hotels in Orlando require someone to be 21, and others 18?

I’m going to Universal Studios in March for Vaca. I checked with the on-site hotels, you have to be 21 to rent a room. Some off site hotels also require you to be 21. I finally found a not so nice budget motel but the reviews were horrible. Then I had to call and call and finally found the Comfort Inn Universal Studios Area. I called them and the man told me you have to be 18, So I booked the room. I’m 20 right now. But how come some require 21 and some 18?

What hotels near Universal Studios Hollywood offer a complimentary shuttle to the park?

What hotels near Universal Studios Hollywood offer a complimentary shuttle to the park OTHER THAN the Hilton, Sheraton, and the Marriott Burbank Airport? As a bonus, do any of them offer free or discounted tickets to the park?

Thanks in advance!

What are the differences of hotels before and hotels nowadays?

Hey! I just wanna know what kind of services hotels back then offered that hotels these days still do offer or stuffs that old hotels used to serve and are now considered as obsolete services by new hotels, it could also be that only a few hotels are still offering those stuffs or they still have it but in a different way…Any answer would really help thank you.

has anybody tried staying in one of Paris’ hotels?
what was it like?XD