I think I understand the whole running it in the middle of the night testing if that's what is happening. The average park guest is dumb. You agree with me too, admit it. If they see the coaster running then the assumption is that it is open. They go to the coaster all excited to ride it. The nice team member who now hates life has to explain it about 1 billion times that it is just testing, opening soon, blah, blah, blah. Most guests although very disappointed understand, some guests complain to guest services, some guests throw two year old temper tantrums.
Bottom line is it creates a negative guest experience to have it "testing" but not being able to be experienced by the paying public. So if you can run it at night I totally understand why they would. Just my opinion!