I don't think i'd be offended or think you were rude or anything, at the end of the day we go to these things for the company.
Honestly though (and I'm sorry if this sounds arrogant because I really don't mean it that way!) i'm surprised that bringing your own meat is considered the norm for so many people.
I don't think I've ever in my life been to or hosted a BBQ and been asked/asked guests to bring meat. Of course bringing your own alcohol seems pretty normal for a casual BBQ thing. And as well as taking alcohol we would always bring something food-wise as well as a gift for the hosts. But it's just never ever come up for me! If we turned up at a friends house with our own meat I think they'd just think we were strange or that we didn't like their food.
I guess everyone does things differently!