it is also the center of balance. you can carry or lift more weight at your sides than from in front of you because your stronger if your balance is centered when you start rather than tryin to get is centered as you lift the weight in front.
we have a guy in the gym that brings in his own trap bar on saturdays sometimes when the big boys do strong man training. it also disconnects and has other attachments to do farmers carries. obviously a custom made bar so that doesn't help steve at all.....