Its just a logo, nothing to do with a pentagram. Also a pentagram lets you see the lines connected to form more then just the star.
I will say not buying something because what others do with it doesn't make much sense. I mean if thats how we live then we shouldn't be on computers or online because child inappropriate content, inappropriate content, murder, death videos...etc are also used by others on the internet. The clothes we wear in america are mostly made outside the country by people being paid pennies who usually suffer through life. Some get killed, some die...etc. So we shouldn't wear clothes either.
BTW I'm just making a point, with that said though its up to us to do what we feel convicted about. So I can't judge on that. Me? I don't think people should drink (alcohol) or smoke at all, so its why I tend to have nothing to do with that stuff or people related to it. But its just my own decision to do so.