Summary: Big guys have big problems when looking for clothes. We’re from a family with big guys, and we always watch them search store after store trying to piece together items that will resemble an outfit. From shirts, pants, and accessories all the way down to shoes, it is difficult for bigger guys to find stuff that fits.
There are several reasons why not many stores carry “Big & Tall” departments. Perhaps the most accepted reason is that the B&T people are not a big enough department to make them economically feasible. The expense of making a dedicated department outweighs the benefit of having B&T customers. Maybe not.