These kind of polls seldom give any real poll about the way how ukulele players hold they instrument. Just who happens to participate.
I like it without any, but it is to me ok to have a strap. A lightweight instrument that can have a lots of support that way.
About guitar, the straps suck for me totally. Classical guitar, no way. An acoustic guitar, no other way than play without a strap at home. A solid body electric, in that case something like fly V model needs a strap definately. But who wants no support a furniture in their daily play? And standing up?
For me as told above I prefer ukes straples, but can't deny the advantage of one, because typically you won't get same support as to a guitar sitting. But to grap an uke and just start strumming, I prefer just take it, also I don't have to worry if the strap fails.