Yeah, it's a fine line, but not to hard to figure out. Most groups make the exact same mistake, over and over:
They'll play one club in town one weekend, then play another club in town the next weekend, then repeat the cycle. The trick is to boraden your playing base so that local fans only get a chance to see you maybe once every 6 to 8 weeks. And make sure you have a new show for the next cycle, not just all the same stuff they head the last time.
During the breaks between the cycles, try to figure out which songs are the most popular and why. Finally, do everything in your power to establish communication between the band and the fans: get their names, and email addresses, and make sure they can get fan gear (albumns, bumperstickers, T shirts, caps, etc.).
Have a table set up at the gig with all the gear for sale, but throw some freebies out to the audience during the show, or give it out as prizes. At this point, you can be outrageous; you have nothing to lose.
It's ALL about getting attention.