I agree that you do have to "put the pax down" when they start being personal. I remember a friday evening prg, we had a stag party of at least 45 pax being difficult, i was being accused of looking at their crotches as we had turbulence. When it came to the final cabin secure one very ugly man decided to expose himself to me and ask me if i wanted to suck it.........i had been on duty for 10 hours by now.........as he was ugly i replied......suck on what........ive seen bigger sausages on my crew meal........result.. 1 embarressed pax and 44 mates of his with ammunition for their whole stay.
I also get the feeling that we are considered as being something that the pax have stepped in and also enjoy being poked when my attention is required
One other thing, there were a couple that had they offered me a go i would have accepted.