the rappers/ballers arent losing money unless they are unsigned/dumb as hell/desperate
the club pays jeezy say $15,000 to show up, have some drinks, play the new single maybe even drop a live song, they may even give him $5,000 to 'make it rain' = $20,000
the club is doin it all jeezy or the rapper/baller is just there havin a good time