ANSWER - You are not the first witch to make such a comment and I doubt you will be the last. Halloween does provoke some pretty strong views. At the one end of the scale is your own viewpoint which sees the Day of the Dead as primarily a witch tradition that does not necessarily lend itself to popular culture. Other denigrators often complain that the publicity of witchcraft detracts from the secrecy of what is essentially a very private path and that it encourages people to jump on the bandwagon and proclaim themselves witches without putting the ground work in. Others also feel that the tackiness of the modern festival takes away the solemnity and respect at a time of year when traditionally witches and pagans are honouring their ancestors.
But (and you knew there was a but coming...) there is also a real positive to such a public holiday. Nothing breeds fear more than lack of awareness and understanding and Halloween is our chance to be a bit more open about who we are and what we do. Demystifying the craft helps reduce discrimination and fear of witches. In many cases and I'm thinking especially Bible Belt America it might be the only time of the year a genuine witch can actually dress in accordance with her path without fear.
Yes there might be some young people who get caught up in the holiday and fancy themselves witches but rather than see them as bandwagon hoppers why not see them as the future of the craft? Today's little girl trotting around on a toy broomstick could be a credible witch of the future, continuing the work that we put into the world. Witchcraft is a path, a craft and an art and these things will only survive if new people are willing to put their energies into it. If Halloween is one big mass advertising event for the future of our craft then I don't personally have a problem with that. Those who are serious about what they do will practise long after the festive spider webs are taken down and those just having some fun will move onto the next big thing - no harm done.
I'd also point out that witches are no different to anyone else - we like a bit of fun. I certainly don't think wearing a pointy hat and a warty nose one day of a year mocks my calling to the craft. There is such a thing as being too serious... Practise the solemn Samhain rituals by all means but if you also feel inspired to have some fun with the kids - do it. There's nothing to say witches can't let their hair down and lets face it - Halloween is our time of year. I say claim it back, welcome everyone and lead the way with style!