They do, however, tend to accumulate in certain areas. In this area of the Delaware Valley, they are known to attack any unpainted or unfinished wooden items. While the females do have a stinger, they are very docile and are not known to sting people, even when disturbed. The males, as with any bee, wasp or hornet, have no sting mechanism.
Carpenter bees are bigger and much more robust than the bumblebees.
Female bumblebees can sting and female carpenter bees have the equipment, but almost never do. In the springtime, the males actively search out the females, and hang around where the females have found some unfinished wood. Most of the congregating bees you see in the early spring, hovering around, will be those males. Male bees are incapable of stinging, and are only checking you out. If you stand still for a minute or two they will forget you are there and leave you alone - unless, of course, you happen to be a female carpenter bee.