The title of this thread has been edited from the original: loyalty by day

It doesn't seem like there is a way to create loyalty programs by time of day. Are there any creative ways to make it happen? 

For example, every $1 spent gives a customer a point. After 50 points, they get $5 free. Our morning traffic is poor, so we'd like to give double points from 7am to noon. How would we do that?