To be honest, unless you're a bass prodigy and you were playing something amazingly cool and unique.. if I saw a random bassist in some club trying to play behind his head, it would make me want to leave.. maybe even throw up in my mouth a little. I say spare yourself and your band of the pagentry. We aren't guitards.
Crowds ,who by and large aren't musicians, generally like this sort of thing and it's fun if it fits the vibe. Theres always the Rush concert to go and be musically impressed.
I am going for it!