I think there is an obscure regulation somewhere in the FCC that says that the quality of dress across television must average out to a certain level. I don’t remember the exact level, but in any case, they generally use soap operas and sitcoms to balance the thing out.
It’s kind of like CAFE standards. I think there is a kind of dress standard exchange so that if a network has too many dressy shows, they can buy dress down credits from other networks. In fact, it is possible for individuals to play the dress down market. I, myself, have actually sold several dress down credits at reasonable prices.
It’s really great because I can show my wife that not only is wearing ratty t-shirts comfortable; it is also profitable. I suspect that there will soon be a gender dress down exchange because there is an unbalance in the level of dress between men and women; not to mention Walmart customers.