Note that the grading systems in most European countries are very different from the one in USA: We use the whole range. No "B is ok, A is good". Here A is mostly excellent, and C is an acceptable grade to get. It's good to keep in mind when researching our universities. So you don't get put off if the acceptance grades are low or if the average grade is low.
It's weird going the other way (from Europe to USA). They told us we couldn't continue the studies if we got below B-, and we were like "???".
I'd like to remark that there's a similar trend that seems to go on in high schools and with college admissions. By all accounts, I've heard that it's not too difficult to attain perfect high-school grades (save for some of the very competitive high schools), whereas that's usually a serious achievement in European schools. There's a similar comparison for the AP vs. IB examinations.
It's weird going the other way (from Europe to USA). They told us we couldn't continue the studies if we got below B-, and we were like "???".