1. They do sometimes have 15 second ads on short excerpts – and I absolutely hate it. The cost just seems way too high for a 1:00 clip. (On the plus side it makes me reconsider if I'm spending my time wisely.)

2. I too don't understand why they play the same one or two ads for the entire movie. It honestly gets annoying, which seems like something you don't want your advertising to do. At this point I just mute them.