I spent 4 tickets in a row right now. All the 4 matches the same trackset. Sorry but this isn't random. Almost impossible!
Since every event has 4 tracksets:
Chance of 1x: 25%
Chance of 2x in a row: 6.25%
Chance of 3x in a row: 1.56%
Chance of 4x in a row: 0.39%
Unfortunately I didn't have a 5th ticket, but I am 99% sure that would be the same trackset
This happens very often. At least 1x per week. But I will take a note here to be more precise if happen again