There are too many horses that have NO SHOT to win in each race. Doesn't matter if their are 10 horses in the races when there are 6 throw outs in every race.
Just in tonight's Pk4:
Leg 1: two 99/1 shots
Leg 2: two 99/1 shots, five of ten over 45/1
Leg 3: four 65/1 or more
Leg 4: two 50/1+ shots
Effectively creates short fields.