Yep. Though I’m as likely to eat the burger without any bread, I will always have mayo.
The finest burger is with onion and mayo only.
Onion, mayo and home-grown tomato.
Not usually.
I make my own special sauce that is a mixture of mustard, mayo, cayenne powder. If I’m out and feeling lazy, I will sometimes just put mayo and mustard on the burger instead of making up another batch of sauce.
no
mayo is gross
Not usually, but sometimes it’s good. I’m mostly a mustard guy, but lately I’ve been slopping some Ranch or blue cheese dressing on. The burger that is. 
My go-to set of burger toppings doesn’t include mayo, but I certainly like mayo on a burger. In fact, I had burgers for dinner last night, and within the last hour or so decided to have some of the leftovers with mayo (for a change of pace).
depends. If I feel like one with “the works” (e.g. lettuce, tomato, onion) then yeah, a schmeer of mayo doesn’t hurt. If I feel like a minimalist one (maybe cheese and onion) then no.
Always. (Peruvian-style)Mayo improves any mammal, bird or reptile.
Never if I’m making it myself, almost never if it is being made for me. Mayo has absolutely no business being on a burger.
It’s an abomination.
Mayo is the single greatest condiment. It is perfection.
Mayo is great. I have a hard time with mayo haters. As they often like ranch, blue cheese, caeser, tarter sauce and other flavored mayos.
Covers the taste of the mayo. 
I only use enough mayo to keep the bun from getting soggy. Sometimes I use butter.
Almost never. Which is odd because if I have any type of steak sandwich instead, I almost always put mayo on those so clearly beef + mayo isn’t objectionable.
Almost always if I’m eating a typically dressed burger (lettuce, pickle, mayo and tomato). Most creative-type burgers don’t need it (ones with grilled toppings like onions or mushrooms). Lately, I’ve been a bit more concious of the type of fats that I consume and have been opting for a schmear of guac instead of the mayo.
I like mustard, mayo AND ketchup! I usually put mustard, ketchup, black pepper and dill pickles directly on the patty, then tomato and lettuce, put mayo on the inside of the top bun and enjoy the mingling of tastes!
I don’t like burgers (other than Burger King junior Whoppers). If I have to eat one at home, the addition of mayo, with ketchup or barbeque sauce, makes it go down really easy.
I prefer 1000 island dressing. Mayo can be nasty to me if there is too much of it. If it’s a good steakburger, I prefer A1 sauce.