I read through the whole thread and first want to thank everyone who gave some very good reasons to submit to portfolio reviews. It seems that there is a disconnect between the first of this thread and the last. Comercial gallery shows are vastly different than competitions or exhibitions with academic institutions or non-profits. I can not possibly see how a gallery could exhibit work and charge admission unless it was a one night performance type of event. I think everyone should look at the exhibition of their work as just that, exhibition and an opportunity for others to see your vision.
Selling the work is another thing, I know gallery owners and to sell requires planning, marketing, lots of things I do not wish to do as the artist.
The only galleries I have every run into that require payment for exhbition are vanity galleries.