We aren't slickdeals and slickdeals is a tiny percentage of the internet.
And Gamestop people have been reading these forums since at least 2004, they've even had an official rep posting here at one point.
I would argue that slickdeals is certainly more used then this site in general. But it’s very unlikely someone from GameStop is watching any forums to look for exploiting glitches to jump on and stomp. It’s much more likely they have a mediocre program that watches the online transactions and assigns someone to look at whatever the computer flags as a potential issue.