I disagree about not charging a callout.
A business doing many small jobs like the OP's breaker replacement won't be viable unless you do.
Boy sparky tells me that there's an issue with too many cowboys, probably no public liability insurance, not complying with OSH regs, etc etc - doing jobs on the cheap.

"Walking away" from jobs that aren't commercially viable is common. If someone is doing those jobs at the price, then there's a problem.