I do a lot of these types of events and here's the thing...
There are usually a lot of organizers, volunteers, vendors, city officials, local politicians, etc. involved donating their time and services. These people almost always get verbally acknowledged at some point during the event, including the DJ. The guilt is usually going to come from being the only person collecting a check among those honorable mentions. If you're not in it for the same reasons as everyone else, that's fine. Make that clear up front and get paid. However, your buck might be stopping right there, because people do talk.
The residual reward of exposure and recognition in front of some of the community's more affluent and networked people is nothing to sneeze at. Take advantage of it. Get out from behind the rig, smile, shake some hands, meet some people and make yourself known. Play it right and these freebies will pay off later on.
