Mike, correct... but it does happen sometimes. Carpenter bees are fiercely territorial though.. and more than likely that's the reason they are hanging out in front of your hives is that they see each honey bee as a potential contender for female carpenter bee attention. Usually they'll just chase the girls around and the girls for the most part just ignore them. I've never seen a carpenter bee try to gain entrance into a hive before though. I have seen bumble-bees do that though, could you be seeing bumble-bees instead of carpenter bees perhaps?