I think a subforum would be a good thing. I think compared to when SPAM was started to now, there just are not that many true SPAM related sites out there anymore, and it's grown to free stuff.
I like the free stuff. My cats like the free stuff. The dogs at the animal shelter love the free stuff. My wife likes the free stuff, I like the big crumbs deposits, etc.
And yes, I can get most of it at Fatwallet, but I can also get most of the Mileage stuff at other sites, and I'm not helping a fellow FT'er with their downline. I don't believe that's a reason not to have it here.
If there needs to be a change then two forums, one for SPAM as it was first meant to be, and one for the other stuff would be my vote.