Answer:
It is a good platform to promote the product anyways. It will attract a huge audience, which will improvise the sales.
As TV series are watched by a number of people, generally in millions or billions, there is a wide reach for such kind of advertisement. As people these days are not only fans of TV celebs but in fact, they tend to follow them also. This assures the sales at a certain level, as people tend to buy what there favorite celebs wear.
This is a good technique to promote the goods, as assures quality of the product, even though it might be marked high as per pricing standards.
