Very short vacations is a very American thing coming partly from protestant work ethics, together with other pro work, anti welfare views. Europeans take a couple of months off.
As to the feeling that if you are out for a month, bosses will see that they can do without you, there are 2 solutions: 1. Be your own boss 2. Create a system that nobody can figure out so bosses realize how indispensable you are.
Banks actually require some to take vacations to make sure someone can independently check your accounts.