We have switched to always dropping off for short drives. If it is under 10 minutes, I will drop off even if I have to be back in 30 minutes because I still get a lot done at home (eat breakfast, walk dog, do dishes) before I head back out again lets say for a morning soccer game. I drop for warm ups and come back for the game.
1 hour stay, 90 minutes or longer drop off. DD normal practices are 3hrs. There are some parents that do stay but they also live 40+ minutes away so will use their in-town time to run errands, work on their laptops or just have quiet time with a book. We have one family who alternates who stays and when mom stays, she always cross stiches and listens to an audiobook. She told me it is the only "alone time" she gets as a SAHM of 3 kids.
We cannot drop off for games as DD's gymnastics meets are all out of town.
One hour or less I usually stay unless it’s in town and traffic is 5 min at that time of day. I use that time to get some steps in. It’s taken like 3 years for me to work up to being able to walk while I wait. In the past I’ve always just sat there and zoned out on my phone or sent their dad to deal with the activity transportation.
DS plays hockey so he has practice usually 4x/wk. The 2 main rinks he goes to are each just a few miles from home, so he mostly gets dropped now. (When he was a bit younger, we stayed for the hour practice.) Though, I did make a pact with myself that once a week, I will stay and walk the perimeter of the rink during practice. I can usually get 3-4 miles in in that time.
DD does gymnastics 1x/wk for 2 hours. It is close enough that she could be dropped off, but she is younger and we don't really know any of the parents or coaches well, so I'm not as comfortable leaving her.
45 min-1 hr I'd stay. Longer I'd drop off, for that distance away.
Two things: If you can find someone to carpool with - DO IT. My youngest is in dance, and we carpool with a neighborhood friend. They mostly take the same classes, and are there 3 hrs a night, 3 nights a week, and 5-6 hrs Saturday morning-afternoon. Carpool is the only was we could make that work, especially when they weren't there for as long as they are now.
Before carpooling, or to other activities, I'd just bring a book, play on my phone, or bring a neck pillow, crank back the seat, and sleep. My kids saw my phone one day when I opened one of the games, and they were SHOCKED at my levels on my game. But I was like, do you have ANY IDEA how much time I spend just sitting around, waiting for you guys while you're at practices/activities? Yeah, I can only read so much, and as someone else has said, those candies aren't going to crush themselves.