Personally, I wouldn't have an issue with it, aside from the fact that the company making the products is probably doing it to save money, but is still charging the full price as though it were 100% beef, and those full prices are being passed on to the wholesalers, retailers, and consumers. I do remember an issue with vaccines as
Eriol stated, but my source is M*A*S*H, and I don't know how accurate that really is.