Dr. Pepper is a type of coke (it's like saying "googling" when you mean to use a search engine)
When someone tells me to google something, I fucking google it. I can't remember the last time I used a non-google search engine.
Genericized trademarks seem to make more sense when there's little to differentiate the different brands--in other words, they're all fucking generic. Kleenex? Band Aid? Q-Tip? Zipper? Frisbee? Kitty Litter? Vaseline? If there is a difference between Vaseline and other petroleum jelly, I don't know what it is, and I don't care.
On the other hand, most North Americans can taste the subtle difference between Coke and Pepsi, let alone the vast difference between coke and 7up.