Hulu used to do it. idk if or when they stopped. But it was the primary motivator for me to buy the no-, commercial package.

(That was till I swore off and went full pirate a few years ago.)

But honesty, I never put two and two together.

They almost certainly were doing it to ramp up the unpleasantness of the commercials to push people to pay more to avoid them.

Fuckers