Fakes/Flakes are everywere. The reason you get lucky when you travel, I think anyway, is that you are only there for a short time, they will never run into you anywhere when they are out and about and don't have to worry about anything awkward if they are cheating on their boyfriend/girlfriend or whatever.
I don't have much luck when I am home, for one reason or another, but the last 2 times I've gone to Vegas for work I've gotten several loads from locals and tourists alike.
Flakes/Fakes are Everywhere. Nothing one can do about it unfortunatly. If the flake out most likely they would have been a bad fuck anyway so count your luck and move on. My 0.02.