In case you’re actually, seriously asking and not just trolling, having privilege and success under capitalism does not disqualify a person from being a leftist. You can’t really criticize a person for participating in a system where if you don’t participate, you starve.
He’s using his influence to organize the working class and advocate for collective action, which is the one tool workers have in the fight against their own exploitation. Even if you don’t like him personally or don’t think he’s part of the working class, he is a very strong ally and has undeniably strengthened the movement.
I think you’re overestimating how much money it costs to produce this stuff. Economies of scale and certain other practices in this specific industry allow retailers to sell stuff at a significant markup even when it seems like they’re giving customers a heavy discount.
But even with relatively large markup percentages, the low price point means retailers have to move incredible volumes in order to make enough money to stay open. So they end up using aggressive marketing tactics to get people to come in the door and start impulsively buying stuff.
My intuition is that those shirts are simply from last season and didn’t sell well enough or they’ve gone out of fashion. The store is using it as an opportunity to put a big 80% off sign out front and whip potential customers into a frenzy. Could also be a scheme to recover costs from online returns. But I really doubt there is anything wrong or even different about those shirts.
Source: worked in clothing retail for a several years