You'd be surprised how many state witnesses are hidden away in unassuming communities. A few years back, a hitman from Philly snapped and outed himself at the Honda dealership he worked at in Carmel. Said he was going to kill a guy. We showed up, got the scoop, Marshals came by picked him up, and he was never heard from again.
I've always wondered what the recidivism rate is of the people in witness protection. I'd imagine it's up there.