What kind of non-engineering classes might there be in a engineering degree? In the UK courses are (or at least used to be - some have gone all "modular") rather narrow in focus - in the 4 year CS course I did in the 80s only one elective class was included that wasn't specifically related to maths, engineering or CS (and that was a rather enjoyable "History of Science" course).
The specific nature of non-engineering classes varies, but most science/engineering degrees in the US will require about 16 1-semester classes spread across {history, sociology, literature, etc}.
This is reduced a bit if you go to an engineering school. I only had to take 9 non-science classes (+ 4 gym classes).
That's true, and it is a specific complaint I've heard that I did overlook in my statement.
That said, I think it's common to specifically point out your discipline-specific GPA (especially) if it is substantially better than your general GPA, whenever given the opportunity (like on a resume).
One obvious complaint is that an engineering student might have 50% of their GPA attributable to non-engineering grades.