Sorry if this seemed like a newbie question...
Is it normal for my standby router to have a bigger outgoing traffic than my active router on a HSRP group?
HSRP affects traffic from the end stations in the subnet/VLAN to the active router. So the active router should probably have higher input than the standby router. But then the routers forward traffic to its destination and the destination sends responses back to the source. Depending on how routing is set up, it is quite possible that more of the response traffic will be sent through the standby router and that the standby router will have higher output into the subnet/VLAN.