As much as I like to support the old timers and old that, giving someone a monopoly is a problem in my book.
I'm fairly new to the scene, but I already noted that SOME paper is a lot more expensive than some other, equivalent paper not prised by photographers... and SOME transparent film too, and that applies to brushes etc as well.
What I'm saying is that diversity - and having several source for material - can never be bad. I do appreciate the fantastic support of the sponsors, but I don't think it's a good idea to stop looking in different places. It's healthier.