I agree with the peeve of folks not keeping their ukes in tune. Other than that, I don't have any peeves regarding what a player does with their uke as long as they are having a good time. The following is not a peeve, but a question:
Why do some people keep coils of string attached to their ukes' headstocks? I've seen gorgeous ukes where the luthier has done beautiful inlays, or slotted headstocks with multiple veneers, etc., only to be hidden by a snarl of strings.
Is there a practical reason for doing this?
I do that sometimes thinking I will change the strings if I don't like them. However, I end up cutting all of them if I don't like them. Secondly, I've had several instances where the string snaps when I cut them short as soon as I put them on. I am not sure why that is but it has happened. So in short, I'm lazy.