I do not think there will be a problem with someone only being able to log in a couple of hours a day - that is already way more than is needed. Like, internally, we assume that on public servers players log in once per day for 30 minutes. That's simply what we feel is needed for 'active' play and is what a lot of our systems evolve around - not more, not less.
I do understand that you feel that this might be a problem on a server that only has a single cook - but if you're on a server with just friends or very small public servers it's totally fine if you change the setting for spoilage if you feel that is something you can't sustain, that's why options are there.
On the average public server that has multiple cooks, but some leaving soon due to one ruling them all (which is one of the problems we try to address) that is no problem though, same on the more active community servers as there is plenty cooks available - and as I said above, it is totally intended that...
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