I mean the minority, which I'm not sure "some" implies. The factors you describe: cheaper, control, health can be seen as the same as cost. More expensive places might taste better, be healthier etc. While I'm sure a lot of people enjoy cooking, I'm not sure many would recreationally cook as often as they need food.
> context
You can have fun imagining the payoffs, only to find they do not appear. Have you ever seen a movie and been disappointed, or played a game and found it lacking. "fun" is not an absolute measure, and review doesn't necessarily capture how fun something is versus how fun you think it ought to be - plenty people give things higher value than their "fun" value, despite claiming to only have done it for fun - the missing value is ideological.
> there is little value in assigning a dollar-value for time that I am going to spend doing something that _I want to do_
Only if there is, some some reason, literally only one thing you want to do. But if there are competing things you might like to do then comparing them makes sense. One way or another, if you choose to watch a movie, or build a sandcastle, you are comparing the two to decide which. Using monetary values is just a more formal way of doing that for larger, less impulsive, projects.