It's dumb and it's there to pander to an edgy audience, but it really shouldn't be a problem. Why does that scene bother you? Isn't it just because that stuff is taboo?
That may be all there's to it, but I bet the fact that it's sexual makes all the difference. Do you think Bucephalus355 would have bothered to complain about it if the scene was of a woman puking?
A) Puking is not anywhere near as disgusting, and you could get equally disgusted by seeing someone peeing on someone else even in a nonsexual context (e.g. hazing).
B) Some people can feel elevated disgust towards portrayals of other people being sexual. In that case, the fact that it's sexual does make the difference, but it's still a disgust reaction.
1. It insults the intelligence of the viewer and indicates the rest of the show will do the same
2. Humans urinating on each other combined with torture is disgusting to the vast majority of viewers, and seeing a scene like that will naturally turn off many viewers. Even Game of Thrones saved the rape?-on-top-of-a-corpse scene for after the characters had substantial development.
On a related note, at what point does "don't judge" end? What if the opening scene depicted necrophilia? How about beastiality? There's nothing wrong with being disgusted by things 99.X% of the planet is disgusted by
To me it's not about "don't judge", but about not treating sexual things like they're special. Notice how both of your examples of potentially over-the-line content are also of a sexual nature.