Probably different reasons from different players. Some don't like the wider neck. Some don't own a five... etc...
For me though, I just never could wrap my brain around playing a 5. I've been playing on 4's 8's and 12's for 20 years. You put a 5th string on there and it feels like there's an extra string in my way no matter which string I'm aiming for. I could probably transition to a 6 string easier than a 5 if I was really forced to.
Don't get me wrong, I like the idea of a 5, but it just doesn't work for me. Doesn't feel natural.
so you can play a 6 string, but not a 5????
