We remodeled our kitchen and put on a garage addition in the past year, so I've spent a considerable time shopping at HD (a dept manager there even knows me by name). I've always been treated courteously and helpfully when visiting my local store in Rochester Hills, Michigan.
OBB, you've had better luck than I have. At the HD in Rockaway, NJ, I can recount 4 different incidents where their employees were beyond merely not knowing something. And, we're far enough away from NYC (45 miles) so as to avoid that brand of nastiness (other merchants in this area are fine).
But, I hasten to add, there are some HD employess that are knowledgeable and considerate (and often female!).