Used to work part-time for Lowes a fews years back. A buddy of mine that I worked with during the day talked me into working with him at nights. The extra money was good. I was originally going to be a part-time delivery driver until they found out how much I knew about plumbing and kept me in the store. My buddy told them so I'd end up working with him (nice guy). Ended up working the plumbing section at nights and one weekend day. Yeah, sometimes the customers can be a pain. But for the most part they aren't that bad. If you know what you're talking about and don't BS them you can usually move on to the next one in just a couple seconds.
The reasons I left were because the managers didn't want to give me any days off (kept me scheduled 7 days a week) and they always kept us late to help the other department "down-stock" their divisions.
You see, while I left my buddy to handle the customers and the department phone calls, I spent the whole night restocking the shelves and moving item from the top racks down (down-stocking). But the night managers won't let you leave after closing till they inspect your area and says it's clean and fully stocked. Of course our section (plumbing) was ALWAYS clean and fully stocked by the end of the night because we busted hump! But it never failed that the managers would make us go to other department and do their work. They didn't do Jack all night and we'd get stuck doing the work. I had to be at my day job at 6 AM. Getting home after midnight got old fast.
My suggestions:
If you take the job tell them up front what days and times you WILL work.
DO NOT work in garden area, construction materials (lumber) or paint unless you enjoy pain.
Custom installs are also a PITA.
If you know anything about electrical, plumbing or power tools they're the easier places to be.
But one of the best areas is appliances. Not a lot of work or as many sales.