Yes, most banks do this now as a way to take advantage of their customers and generate more revenue. I had it happen once on a road trip -- you know, the type where you stop frequently and purchase $2-$3 of junk food or drinks all the time -- and ended up with hundreds of dollars in overdrafts on what would have actually only been about $20 of overdraft.

Several banks are being sued at the moment in class action suits for this behavior if I recall correctly. It's an unfair tactic that takes advantage of customers.