No one has ever asked me to, either. What they do is trust me to know the right tools for the job I'm doing. I have done auditions for New Country bands where the first thing out of the BLs mouth was "Oh, I'm so glad to see you brought the five-string, most people don't."I've been playing for 40+ years and no one in any gigging/recording situation has ever asked me to play a 5 string.
So they do notice even if they don't always ask.