Which beggars the question, how do you get established as an unknown band?
Simple. You play for free until enough people have seen you that you have built up a reputation and a following. Then you can charge for your efforts.
These kind of threads happen quite often on here every time playing for free is mentioned, and they almost always turn into a debate on whether or not band should play for free in the first place. It's pretty pointless really.
How does anyone ever get to the stage of getting paid, if they don't first play for free to build an audience?
Ok there are exceptions with professionally trained musicians with musical degrees. But then they're unlikely to be playing down the Dog and Duck for fifty quid a time anyway.
There are two totally valid sides to the arguement and neither is right or wrong.
I can see why professional musos wouldn't want to lose work to bands playing for free. I can also totally see why hobby bands, or bands trying to build a following would do so.
It's just the nature of the game.