This is all sounding awfully familiar, but I'll chip in my similar story anyway -- entertainment company brought me on for two shows a week after the boss enjoyed my "singing bartender" shtick on karaoke night at my old job. I kept working menial day jobs after my bartending gig went under, still averaging a night or two a week with the karaoke.
As it turns out, my karaoke boss wasn't the greatest business man in the world. He tried getting me to take pennies for my shows so he could make more money, and his exceptionally abrasive personality got me terminated from potentially lucrative gigs. As fate would have it, however, the company I was working for originally splintered off from a larger company. The owner of the parent company took a shine to me and negotiated with my boss for a trade -- all of a sudden, I was working better venues more often, and my minimum wage day job seemed unnecessary, so I ditched it. The private parties and weddings started to roll in, and now I get 1-2 nights off a week at most, between parties, regular gigs, and things like trivia and open mic nights.
So it's a business, but it's not MY business. I'm in talks to take over for my boss when he leaves the karaoke game. He's vowed that he's gonna call it quits by 51, which is about this time next year. Figure it's time to crap or get off the pot, career-wise (28 and married, no kids), so I'm thinking of buying the company and keeping his handful of other KJs on. At which point look for me on here begging for guidance.