Why Do Hambugers Taste So Lousy in Other Countries?

I was in Toronto the other day and made the mistake of ordering a hamburger. Man, it was terrible; I could only take a few bites and then let it alone. It had been a year or so since I'd traveled outside of the U.S., and I'd forgotten that you just don't order hamburgers in countries outside of the U.S. There's an amusing subplot dealing with hamburgers in Whit Stillman's film, Barcelona. In it, a couple of Spanish women use the popularity of hamburgers in the U.S. as the exemplar of the bad taste of Americans. The Americans in the movie object, pointing out that hamburgers outside of the U.S. typically taste terrible. The film ends with the Spanish women, now married to the American men, biting into their first real (i.e., American) hamburger, and loving it.

But what I don't understand is this: Why do hamburgers taste so terrible outside of the U.S.? I figure it must be either what they feed cattle in other countries, or perhaps the cut of meat that butchers use to make hamburger in other countries. But whatever the cause, hamburgers taste terrible outside of the U.S. Even when you're just a few miles across the border, like Toronto.

The thing is, I ordered prime rib at another meal (my publisher chose the restaurant, I would have gone for something other than beef in Toronto - I did have some pretty good Indian food while there, so this is not an anti-Toronto thing). The prime rib wasn't bad at all. So why would the prime rib taste just fine, but the hamburger taste so terrible?

Go figure.