Premium linear channels in the US (think HBO) do this as well. It's an artifact of programming blocks -- you want your movie/show/sport/etc. to start on the hour or half-hour, but the thing before it rarely will end when you want it to (a few seconds of slack time to switch to the next item). If you have some small-enough unit of time left between the end of the movie and the start of the next slot, you either commission a bunch of micro-length shorts or you run internal promos to fill the gap.