Some do, most don't. A lot of guys get compensated by starting off as sparring partners for well established pros. Depends on their life style really.
There is no reason that they wouldn't but if you have a big fight coming up you might want to take the day off.
Of course....even as dishwashers to pay for the rent at the gym / membership.
even some ufc fighters have day jobs.
i mean jobs like carpentry and plumber blue collar jobs
