For two reasons:

First, to avoid disputes. If these trademarks appear in these programs, or even if it is negative information, the merchants have not been consulted. consent, this is likely to cause unnecessary disputes and conflicts, causing trouble to the producers of these TV series.

Second, usually the trademarks that appear in TV series are sponsors of these TV series, and appearing in TV series is also advertising and promotion. For merchants who have no sponsorship, that is, no money, there is no need for the TV series production team to provide them with such free advertising.

So we use mosaic to cover the trademark or business name.