Sorry to hear about your poor experience, but your story is sadly common at these crappy stores.
If they told you that this was the right bulb for your vehicle (or if they told you that any product would do,what you wanted), then you absolutely have the right to a refund. Unfortunately, you would have to either convince them to,do,the right thing (not likely), or sue them (not worth it for a $44 part).
Other than that, customers have very few rights. If the part was defective, you have the right to,a new one, or at the very least to settle for a repaired one (not likely with a bulb).
You have a right to fair, honest, accurate pricing.
But the staff and even managers don't have to be friendly, nice, or even civil. Unless they do something criminal (which they sometimes do) or violate a Charter Right or something, your only options are to complain, to,warn others (as you have done), and to shop at a competitor (which they keep saying they don't care about - they can abuse customers 'till the cows come home, and there will still be a line-up at the till 24/7, for eternity, so they claim).
Any store can ban any person for any reason. You have no right to shop there, and they have no obligation to serve you (but, gee, don't you think they'd WANT customers??)
I say: count it as a $44 lesson in who sucks, and take your valuable loyalty to a merchant who will treat you as you deserve: a valuable human being.