I just bought a pond pump from Harbor Freight. The cashier informed me that once the box is open the store will not handle returns, it has to go through the manufacturer. Boo.Exactly the way I feel. I guess Home Depot was losing money on their tool warranty service. That's too bad.
We recently got a new Harbor Freight in town, and from what I understand, they will take in and exchange tools if still under warranty. Some tools you have to buy an extended warranty, but other tools have lifetime warranties. Depends on the brand.