Yes they do. Its called "True Blue". Its a points-based system where for shorter legs like JFK-BUF you get 2 pts each way. There's medium legs like the JFK-Florida flights and then 6 pts each way for longer hauls like JFK-LGB or JFK-LAS or SEA, etc. You get double the points for booking online as well. So if you make 4 longer flights and a short obne, you get a free ticket! 100 points gets you a free ticket. Its a simple system and in my case, it works. I've flown since the program started last summer and have 89 points now.