Is this how it normally works when a bounty is placed and no answer is received?
Yes, this is the expected behavior. Note the following from the Help Center's Bounty Section
All bounties are paid for up front and non-refundable under any circumstances.
A bounty may attract more attention, and possibly better answers, but it does not guarantee either.
7As someone who's bountied more than once and not gotten answers, this is true. :P– Nathan CDec 26, 2013 at 15:39