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In America elbows seem to be frowned upon slightly less (elbow shoves/forearm shoves are not often called), I think.

Taken from the NAH ruleset.
9 - Permitted contact and restrictions

9.1 - Body-to-Body contact:

Shoulder-to-shoulder contact and the use of forearms is permitted.

I don't know why they allow it, but it's not frowned upon at all.