Yes, bounties can be awarded to community wiki answers.  The restriction on reputation gain applies only to voting.  See this Meta post: https://meta.superuser.com/questions/263/does-bounty-apply-to-a-cw-question.

The thread linked in that Meta post was subsequently deleted (visible to 10K users).  It had 5,472 views, the question had 34 upvotes, it received 62 answers, the accepted answer (and bounty winner) had 109 upvotes.  And it was the poster child for an off-topic question (hence the deletion).