Well Pips, when I was in England pretty much all the ketchup that I tried in restaurants and the school cafeteria was seriously gross to me. I think English ketchup is way sweeter than what Heinz makes.
But, we just buy Stop and Shop brand ketchup. I always bought Heinz, but Stop & Shop's brand tastes just the same.
According to Holby (who works for a grocery chain) large companies like Heinz, Proctor & Gamble, etc are the ones that make store brand items. For the most part they use the same product, just with a different label.