I've never figured out when you break the pattern by knocking a barrel you aren't DQ'd but get paid a %tage of the purse???
.... 12 of 40 riders knocked a barrel in the finals...
Their race, their rules. If you don't like the rules, you don't support them. Or you can produce your own race with the rules you want. Lots of horses at D&D got checks that didn't necessarily deserve them under normal barrel racing rules. Lots of blown barrels and they still drew really nice checks.