First off I want to thank you for being culturally aware enough to consider how (even possible) cultural appropriation could effect and offend people from Native cultures. So many people don't consider it at all (or think our feelings don't matter..ie several of the others posters), and I am always so happy and grateful when I see people take our feelings into consideration.
Am I *personally* offended by the use of un-authentic dream catchers? No, I'm not offended, but then again I am not from the tribe dream catchers originate, nor can I speak for all Natives.
As Asdzani pointed out, it just gets annoying when people use dream catchers in the way weren't intended to use. Such as tattoos. I don't find tattoos of dream catchers offensive, per say, but they certainly do make me roll my eyes.
As Asdzani also pointed out, feel free to sell the dream catcher if you'd like. If you want to be careful about offending Natives don't label the dream catcher "Native American" as it's not, since it's not authentic.
And DeeAnna does not speak for all Natives, as most Natives would frown upon non-Native taking up our customs and beliefs since that leads into extreme cultural appropriation and the bastardizing of our cultures..And most would certainly not compare the use of our traditions to eating Chinese food.
But again, thank you for asking!!