Oh my god, look at that! It’s a poster for a comedy without a white background! So they are allowed to use other colors. Hmmm.
So, we have established that I like that the poster went with a non-white background. Let me add to that that I enjoy the generally retro look they are using here. But the truth is, with a poster like this it really all comes down to whether the depicted characters look like people you would like to spend a couple of hours with. And for me, the poster works well on that level. Those guys are obviously clueless, and they are clearly going to get themselves in some awkward situations. But I immediately empathise with them and I’m also quite curious to see how those situations turns out.
Sense of humor is a very personal thing, so I wouldn’t be surprised if the poster just made a lot of people cringe. But you can’t please everybody, and with a small comedy like this one you really don’t have to.