Dealing with the public can be a challenge. You need to be thick skinned at times. Don't take their rudeness as a personal attack. If you don't enjoy working with the public, maybe you should try a different career.
Yeah. I'm in school right now, so I don't have much choice but to work in retail at the moment.
Learn to laugh about things like this, and the people who are really rude. If you want to know what pisses me off, it is when I am in a store looking at something, and a staff member comes by and gets in front of me because he has to get at something else.
You might not have a lot of choice about where you work right now, but you do have a choice about how you do your job. Keep a positive attitude and always be nice to the customers, because without them you would not have a job. Make their lives better and yours will be better.
Another tip, don't repeatedly walk up and offer help. Try to catch people as they walk in, welcome them, and ask if they need help then. If they say no, just remind them that you are there when they need anything, and leave them alone. I know some stores prefer that staff keep asking customers, but I find that annoying, as do most people I know. If your manager insists that you ask people more than once, try to make it less of a hassle by letting them know you are only doing it because policy requires it.