I would say, go for it, bbc, and if there is anyone there who seems disapproving of your stand, just grin 'em down.

As an aside...it's been years since I've seen live jazz, but was a real afficianado as a kid in LA in the 50's when West Coast Jazz was all the rage...and I never saw jazz combos, from Brubeck to Mulligan, using real sheet music. There may have been a few cheat cards drifting around that I didn't see, but most of those guys played with their eyes closed.