This is BS. The start, middle, and stop bars on a UPC are not 6s. In fact, the lefthand six bars are the reverse of the righthand 6. try harder.
Maybe you should educate yourself further on the composition of upc bar codes and how they work. Here is some info on how the modules actually work. A number is represent by 7 modules, a righthand 6 is bar(1)+space(1)+bar(1)+space(4). a lefthand 6 equals the reverse space(1)+bar(1)+space(1)+bar(4). guard patterns are not 7 modules, the are 3 or 5 in the case of the middle guard, therefore it is impossible for the guard pattern to be a 6. FUD.