Fewer gigs. more money total.
Current main band is 6 people (including full time sound guy), so we were never cheap, but our cheapest gig is now double what it was 5 years ago. Many are paying 3x what we used to charge. We're completely priced out of bars, and many of the clubs we used to play are either not booking us or are booking us less often (and making more of an event of it). In turn we're getting booked some places that didn't look at us before, but we've probably cut our number of gigs by about 1/3.
But the numbers add up - 3x£ x 2/3 gigs = double money at the end of the month for less work.
As people have noted of course it's all dependant on having the product. But even with the greatest product a local bar can only pay you so much.
There's also the "medium latte" theory of pricing. Coffee shops offer 3 sizes: small, medium and large. Unless you're a regular customer, or work there you have no idea how big those are. You don't want to look cheap, or greedy so 90% of people go for the medium. When we're booked through an agency, the agent typically offers a few bands - you maybe don't want to be the most expensive, but the cheap band is there to upsell people to the mid-price band.