I'd like to know how the developers implement the mechanic of having infinite rewards after level 20 in the tracks if the points to reach level 20 are practically counted towards getting level 20. If you don't get the points in the HUB or don't complete one or two missions, there's no way to reach level 20, let alone get points to get anything from the infinite rewards.
In other words, the mechanics are only there to lessen or disguise complaints about weapon parts or to justify the purchase of premium and elite categories on the trails.
In practice, these "infinite rewards" are useless.