keep in mind, most of the people working in HD are either new to the work force, or semi-retired. My HD has two part-timers that are licensed electricians, retired. Those two are a wealth of information. There is a plumber that works on the weekends, he's not a friendly cuss, but he knows what he's talking about.
Now, in the flooring dept. and the building material, those kids are just for stocking and moving heavy stuff. The service desk has 1 guy that was a job superintendent before he got hurt, he has some good info on spec'ing a job (board lengths, and hardware), but he don't want to be there so he gets grouchy sometimes.
Try to keep in mind, these are people too, and they might have been dealing with people that might have been having a really bad day and took it out on them. And, it might have happened 50 times that day, before you got there. So if you walk up and ask a question that he has answered 52 times already that day, he might seem a little short with you. He also has another job to do. He is expected to keep the shelves stocked and clean, which is hard to do when he is answering the same question over and over.