There is a recent question Which universities teach true infinitesimal calculus? , suitability of which has been questioned by several users [I personally do not see in this question anything related to "research level mathematics within the scope defined in the help center"; it explicitly asks for names of "schools, colleges, or universities [which] teach true infinitesimal calculus", and the current answers to this question consist of nothing but lists of course numbers]. The OP placed a bounty on this question and has accepted an answer; however, after an expiration of the first bounty he has now placed a second one. It seems to me that the only purpose of this is to prevent other users from voting to close this question, and I am wondering whether such (ab)use of bounties is really fair.
It is an abuse of the bounty system to place bounties in order to prevent a question from being closed. There is no mechanism to fix this automatically since any mechanism to remove bounties (with or without refund) would be a source of even worse abuses. Therefore, the task to fix such abuses is left to site moderators who have the ability to remove bounties and, when necessary, take other actions to restore the usual user moderation system. See this meta.SE question for a discussion of this issue.