The other reason we as a family stayed away from the Potter books was a plot synopsis we read when the first one started making waves. There seemed to be an underlying message that adults were not to be trusted and lying and deception by kids were ok as long as you had a good reason. We didn't want our kids (young at that time) to get that message. They are old enough now that it wouldn't be a problem and if they were interested in it we wouldn't have a problem, but at this point they are not even vaguely interested in the whole Potter hype. (They are more interested in Star Wars, Monty Python, Hannah Montana, etc.)
While I completely understand the desire to avoid that which is overhyped and grotesquely popular (I myself went straight out and bought black headphones to use with my iPod). I will say this in defense of the Potter series: do you know anyone, anywhere who’s read them and didn’t like them?