Well, one has other things to do in life besides working and punting, no?
After work, you might want to have a nice meal, hit the gym, play team sports, hang out with family and friends, watch a movie, etc.
You're a lot more likely to be engaged in activities with other people during "waking hours" simply because those other people that you do the activities with would still be up.
Besides, if you're like me and like to prep up for a punt, you wouldn't punt right after a meal. I'll need at least 3 hours after my dinner to be ready for it. So a night time punt for me is rarely going to happen before 10pm.