I noticed this when doing time trial on Peach Beach on Mario Kart Wii, the Cataquacks don't chase you down unlike in the races where if you drive too close to them, an exclamation mark appears above there head before they run up to you and flip you into the air. In time trial, they still flip you up into the air if you hit them but they don't chase after you or react which is weird. Why is this the case?

I don't know if it's the same for Peach Beach in Double Dash though. I wonder if I've made a discovery that wasn't known in the Mario Kart Fandom.