My theory is if people you wouldn't normally invite want to come (as a few have asked me to). I've told them that the limited factor is people at the reception, so they are welcome to come and take advantage of the group rate - however they may not be able to attend the reception. That way they know ahead of time and won't feel left out, the people I really wanted are still there can still have a more intimate dinner and everyone and can still take advantage of a nice vacation.