Maybe folks do it like me, when faced with the choice of buying a fretless, they go to upright instead? At least that's my impression.
I did get the fretless first, but my wife bought me an Upright for a special occasion because I always wanted one. I consider them two different instruments. Not giving either up. But I will readily admit the fretless is much easier to carry and go up and down stairs. Upright is also a much bigger financial commitment. Both those things would probably discourage some. For me I thought Upright fulfilled a jazz role.
