Old School Surveillance?

So this am I look out my hotel window. I’m on a sort of ground-floor/flat-roof thing, w/ a somewhat sketchy patio door leading out. And what greets my eyes? A few cigarette butts, a discarded lighter, and a pair of tighty-whiteys. So, uh, what sort of party was ongoing last night outside my window (long enough for ~5 butts)? Old school surveillance it seems, which was ‘clothing optional’.