I'm not sure if it's blatant race fixing, but you'll see more 2nd,3rd,4th choices (horses between 3/1-10/1) get totally noncompetitive drives at Hoosier than any other track - so that they can drop in class and win the next week.
Is there any track where the difference in class levels is so severe as it is at Hoosier?
Look at Friday night races 13 and 14. NW5500L4 goes in 1:51.3, very next race NW9000L4 goes in 1:49.0. That is a 13 length difference in two adjacent classes that horses jump between every week. The discrepancy is just insane.