I run a bug bounty program and I don't mind report for small issues. It's true that most report from "beg bounty" hunters are noise, but we've acted on some reports a few time. One time, in particular, a researcher broke something which alerted us to a serious issue, while not understanding themselves what they had found, we still paid a fair bounty on the finding since we would not have found the issue without the action of the researcher.

It also helps that we have very clear rules and defined scope: we've put out of scope the usual suspects and researchers rarely argue when we point out they should have read the rules better before submitting.

Regarding bounties, my yardstick rule is that if a report made us reconsider our practices and change something on our side, then it's worth a bounty, even small. If not, then no bounty far ya, simple as that.

Also, I don't remember getting a disclosure report where they would ask for money before disclosing the vulnerability, I don't think it's that common. Still, this would go straight to the spam folder.