Over here the protocol (on the originals circuit) is generally that the headlining band provides the backline (drum shells and cabs) and you bring your own head. No head, no gig. I bring my head, my own IEC cable, my own speaker cable, make sure I treat the other guy's cab better than I treat my own.
On a guitar playing gig recently the band before us had a Marshall head fail during their soundcheck and asked for a loan. Given the circumstances, I said ok and loaned the guy my brand new €1500 Fryette head, partly so I could get to hear it out front. He didn't mess around with anything, played his set, all well and good, but then didn't bother to even say "thanks" afterwards... just really sucked the good feeling out of what I thought was a fairly noble gesture on my part. Next time, ask my balls.
As for the O.P.'s situation, if it's the promoter who wants it to cover one of his line-ups and isn't prepared to cover damages, then tough sh*t to him, end of story. I'd have no issue at all in telling him where to go. If he can find the money to hire the venue, then he can find the money to hire backline too.