Functions and pubs will never pay enough to make a living, and if some bands manage that, then fair play.
For me, gigging is all about the enjoyment. I dont do it for the ( small ) amount of money involved. Therefore hassle is not what i want or need. I avoid GK pubs at all costs. If a venue doesnt pay cash, i'll move onto one that does. Less gigs ? Probably , but it doesnt bother me in the slightest