Waiting until you're out may not be the best plan. Even if they have an off-brand, low quality supply of something you want, it'll be Limit Two!
Senior Hour has the main advantage that the store restocks at night. You may get a chance to get what you want, of the brand you want. But you'll only be able to get one or two of it.
We find ourselves shopping more often, not less, simply because we use up the ration of bread, milk, eggs... Our city is large enough that we have several chains of grocery, plus WalMart - and they all stagger their Senior Hours such that there's one every morning somewhere.
Ahh common sense, IMO
