True, though you don't know if it's worth it anyway until you spend the time to do it. Just because you make $200 with your (established and known) site doesn't guarantee someone else would just by copying it.
I do get your point of view though, and it's fair enough, I just think the risk of someone copying a site they see here (and hurting that site's bottom line) is minimal.
I doubt you're going to copy every site on this page and I know I'm not, and yet they collectively bring in several thousand dollars a month.
Anyway, good luck with your site, whatever it is. :) And to everyone else who posted.
I think these kind of threads are really interesting, mainly just to see the different kinds of sites or apps people are making, but I think they serve as an inspiration for people to create something themselves (not just copy), and I'm glad people are not shy about posting what they're doing.