Every band when they start out have gigs where piss all people show up,or no one for that matter. See that as an opportunity for your band to really get your set lists down like a bastard and do some major improvising on stage to stretch your bands chops.Where as most gigs might limit a lot of bands in this regard.
Think of all these gigs as vital regardless if one person shows up,or 500.You should also tape the shows where no one comes out as well.Tape them to Analog instead of digital.You'll get a better feel of where your band is at in every little nuance of their playing more than digital recordings.Sterile recordings like digital don't tell the whole story.Analog does--with every riff,texture and tempo.These gigs will also give your band a chance to free wheel,improvise and become the band that takes your audiences on a journey.Real fans of your music will love your band if you take chances and are serious about playing at higher levels in your given genre,which I hope is Blues,Rock or Country.
These gigs will also give your band a chance to include snippets of other genres that complement your music.Recording those gigs are like an NFL football team that watches and studies their game tapes, then makes necessary adjustments and tweaks to get better,practice and play like a bastard!
You'll take your music farther and your fans will love you for it!!