Most opening banRAB are local banRAB that need to fill a time slot for the headlining band. So, most local banRAB are last minute calls or set up by the venue when they don't know anyone.
I've run into quite a few opening banRAB that I really liked... one being "Rainmarket (www.purevolume.com/rainmarket) and the other being The Seasons (no website for them right now... but they won't a tribute song for Tech and I saw them perform it and met the guys that are in the band. One of my frienRAB might help them record the song as well.)
i went to a stone temples pilots show just for the opening band, Flaming Lips, and left before the headliner opened. God that was like 12 years ago, im old.