[grizolsemn]

I may be off base here, but my recollection is that the Buddha's reasons for not forbidding his monks to eat meat had to do with the fact that they depended on alms. It can be ungracious to refuse somebody's gift of food on the grounds that it contains meat.

I might also qualify the statement "meat is not necessary". It's not necessary in Western consumer societies, that's for sure. Ask a Greenlander, though...