Not to generalize, but europeans and americans tend not to have the same definitions of field knives. When europeans envision a large knife, the idea seems to be saber-like, owing to the rich cavalry traditions which formed many nations on the east side of the "pond". The land, woods and bush had been sculpted and tamed for many centuries. Game animals and domestic animals tended to be smaller and less dangerous and thus, the knives tended to be thinner and lighter. Americans tended to use large heavy knives due to the traditions of the frontiersman who, out of convenience, tended to use their knives as axes.
As I spoke with a few european friends, I came to realize that on average, they felt that a 6 or 7 inch blade was a "big knife". Here in the states, as one of my texas friends say "if it ain't as big as my arm, it's just a pocket knife..."
So, in the absense of large, or better knives, the Glock is a good field knife.