The idea that time is fungible is misleading. I can only drink coffee using my before noon time, or else I take away from the utility of my night time. I’m less productive in the time immediately after a big meal. I can only smell the roses for 30 or so consecutive seconds, and then need a break.
As human beings, time isn't really fungible. I can't wake up at 3am, choose to be productive for 45 minutes, go back to sleep, and then take a 45 minute nap later on in the day. If I stop myself from watching an hour of TV, it doesn't mean that I'll gain an extra hour of productive time tomorrow.
I think an interesting question is whether we are respectively good judges on the "real" value of those ten saved seconds vs more abstract quality of life issues such as mental health or reductions in stress.
Because it's fungible. If I save 10 seconds, maybe I get to keep those for myself.