The players wages come at least in part from the sponsorships, as a core element of the clubs turnover, do they not? It’s ridiculous to think the paltry number of fan shirts a club like Leicester city shifts is worth much compared to the millions of eyeballs from the players wearing it on TV.
But fine, the kit _might_ need to be more expensive (assuming we still want to be creating multi millionaires out of blokes who kick a ball around, while 3 million kids in this country live in poverty). Even so, I was actually agreeing with an earlier poster who said we should have access to ad free kits *even if they were more expensive*!
As for why a piece of polyester should cost what it does, I can only speculate…