Morally indefensible like so many things in the modern world, but the cheeseburger is a work of genius. As yyaldrin says, it's so much better than almost every hipster burger place, most of which are awful and full of people who don't actually like food (only place I thought was genuinely good was a place in LA called Umami Burger or something. Actually, a lot of vegan burgers are very good, since it's all about the condiments). I go to McDs a handful of times a year.
I had one of the banana milkshakes the other week, and it was nirvana. I don't know what's in it, and I don't want to.
Burger King leaves you with the horrible mouth-colonising taste of that fake 'flame-grilled' spray they use. Grim.