Interesting observation Carol. I haven't been watching much action in the other conferences to notice the difference. I don't have any definitive answers for you...only my own personal observations as a sports fan and a USA hockey official.
USA Hockey does not make any requirement/recommendation on the matter. Personally, I have my name on the back of my shirt. But when I order a new shirt, I will probably leave it off. Just not that comfortable with all those hockey parents knowing my name, I guess. Not that I've had any issues in 12 years...
I can't picture officials from other collegiate and pro sports with names on their shirts. Football...nope. Roundball...nope. Baseball...nope. Nor do I think NHL officials have names (but I could be wrong).
With all the crazies out there these days, I get why they want to make it just a little harder to personally identify officials.
Gary Thomas