I think one major thing they have in common is the cheesiness, same ridiculousness and everything.
True, there are few really good horror films, most are quite funny instead. But then again me and a friend o' mine are the kind of people who can find great enjoyment in seeing people getting torn apart in the movies, so perhaps we're not really the perfect horror audience. Still most are humorous or simply incredibly boring to me (for example the grudge am. version, I could actually predict the entire movie while another bloke from school was so terrified he couldn't sleep for a week).
This does remind me of 'nother story though, my little bro' is someone whos was always talking 'bout sex and the such, so a couple o' years back me and my mom saw a bunch of sex mags at the market. So we bought it and went to give it to him while exclaiming loudly "These sex-mags are for you Dave" needlessly to say he first ran like hell, and afterwards was quite embarrased (he did however put the posters from those mags on his walls and door, probably to regain some of his pride).
As for the guy in the train? Well just strangle him or something. I mean if he wants to watch lolicon it's his choice and that's fine by me, but don't do it in public. That kind of stuff is just pathetic.