SiDi:
1. I doubt there is anything more than coincidence with the parallel to Johnnie Walker.
2. Having been in the store before, I found the Baal Haboss (who walked from his Gemora to service me, to be quite eager and ready to respond to my questions. From an earlier conversation with him, the difference is probably in the quality of the fabric (percentage of cotton to synthetic fibers).
3. If you do get to speak to the boss and to ask him something, please relay a suggestion that they design the sirts with an extra millimeter of fabric in the upper left sleeve to accommodate those who wish to lower the sleeve after putting on tefillin.