I have played against chess hustlers 5 times in Washington Square Park, caught 4 of them cheating on the spot, and figured out the last one at the end of the game. I'm not an amazing chess player (~1500), but fairly comfortable playing blitz (a bad hobby from when I used to play chess in school). I walked away in disgust each time, and one of them had the guts to threaten me and insist that I was the cheater.
Chess hustlers are phenomenal at cheating, but only okay at chess. These are not admirable people dedicated to a skill. These are grifters.