Yes, BUT they are typically using the organizer's resources to do this, especially on live streams. It's not the cheapest or easiest thing to set up. A lot of the tournament itself comes out of the organizer's pocket.
Viewers came for an asskicking GF, they get a casual match. Natural offense, but they didn't pay for the event.
Other competitors want to see the top 2 go at it just they might have themselves, and get a casual match? Again, natural offense, except they paid to attend a tournament, not a casual, and their money is now going to them.
The organizer takes time out of their life to plan the tournament, devoting their time and resources to make the whole thing happen, maybe even putting their own money into the pot, and supervise it all just to see the last two guys dicking around, wasting his bandwidth, energy, and overall effort on a casual final? Lord have mercy upon their souls. They actually have a right to be pissed.