Balaclavas in Baseball?

I am watching the baseball game between the New York Yankees and the Boston Red Sox http://mlb.mlb.com/home.  The weather in New York City is cold tonight, and I am seeing many of the Boston Red Sox players wearing balaclavas http://en.wikipedia.org/wiki/Balaclava_(clothing).  It makes sense to me, but I am not sure I have seen that in baseball before. 

I am a cold woosie.  I have good warm clothing, and if it is the least bit cold outside, I wear my winter coat, a funnel scarf http://www.ebay.com/sch/i.html?_nkw=funnel%20scarf&clk_rvr_id=464854481672&adpos=1o1&MT_ID=69&crlp=24074180405_2416792&geo_id=10232&keyword=funnel+scarf&adgroup_id=%7BADGRP_ID%7D&crdt=0, and sometimes, another scarf.  I use gloves, and when it is very, very cold, I will use a pair of mitten over my gloves. I have plenty of warm clothes.  There is no reason for me to be freezing cold in cold weather.