I agree that $300 for an authentic jersey is excessive, and even $80 for a replica is steep. At the same tme, there are two things to consider:
1.) The Bills store employ people in and around Buffalo and the Bills keep the revenue that they earn from pro shop sales, improving their financial viability.
2.) All the Chinese do is steal American ideas and in turn sell them back to people willing to pay for them. Buying from them is not too much different than buying from a drug dealer.