My usual strategy is pretty close to Jenn's as I prefer to shop only once a week. With a heavy dose of Rachylou's "substitute" strategy - my family are used to me announcing a recipe with all the caveats on what I've substituted!
In normal times I had people over for tea (dinner) once a week (at least) and usually shopped on that day so the fridge would be full and then decrease over the week. The numbers coming over would vary, so sometimes there'd be leftovers and sometimes not, so I usually built in enough pantry items in case I need a meal the day before shopping.
This year we had some nights when everyone or most people were out (eg youth group) so that helped. That's all stopped now, and the week it stopped I wasn't prepared! Slim rations that week all round.
However like you, I'm facing issues in the current climate. Shops are limiting the amounts you can purchase of items. Some items are out of stock - we've had to go twice a week sometimes just to get enough. This week the shops were better stocked and by going to two in the same centre I got enough milk to last the week (for 5 people who drink a lot). Last week, one of the shops had none (fresh) at all.
I do have stocks at home - I didn't hugely mass purchase, but for a few weeks we did not use any canned/dried products at home so that my normal amount per week added up. Some meat in the freezer too, so if we had to we could survive for 2 weeks without starving. And yes, I have a separate freezer, which I use a lot anyway
However I don't want to use those stocks at the moment. The situation in my state of Australia is not like Seattle - only 8 cases have been untraced. We have very strict quarantine and border controls. So I don't deem the risk of going weekly for food (with appropriate hygiene and distancing) all that high for a healthy young person for me. Delivery here is only provided for the higher risk anyway.
If we used up all the food by not shopping for 2-3 weeks I'd be worried that with shortages and item limits, I couldn't replenish for even a week's worth at a time when it could be worse.
Happily we are fine with loo paper. We had an existing bulk sub order for charitable reasons, and they've kept it up - we've been able to help others by giving it away (though shops are now supplying in limited amounts as well.
Also, on milk - I often freeze it and it's fine!