I was on a flight a few weeks ago with one large hen party and two different stag parties. All were dressed up in 'tour' t-shirts or fancy dress, most were drinking in the security queues. The rowdy behaviour started while the plane was on the runway (one hen produced a speaker and started blasting out club tunes) and went on for the entire flight, with the hens and stags goading each other on - probably because their 'tour t-shirts' made them immediately visible to each other. It was absolutely grim for everyone else, particularly parents with little kids.
When we finally landed, there was a delay in disembarking which turned out to be because the pilot had called the police to deal with the worst behaved stags. There was a muted cheer from the rest of the plane when they were removed. I sympathised with the cabin crew as we left and they rolled their eyes and said, welcome to our summer season. And this wasn't even a known party destination, just a normal European capital city.