That dude basically gave you a free class right there at the register, which is wild when you think about it. Funny part is those old hardware guys never say it mean, they just state it like a weather report and then hand you the fix. I had a plumbing guy do the same thing to me about my shutoff valve, and honestly I'd rather get the brutal truth than have him nod and let me flood my house.

That bit about the cabbage getting sweeter on day three is real, that's the whole magic of it. Something happens when it sits in its own juices overnight, the sugars come out and the texture goes soft in a good way. I do the same thing but I add a splash of vinegar at the end of each reheat, just enough to wake it up, and it's like a brand new dish every night. By day four I'm usually throwing the last bit over rice with a fried egg on top. The savings stack up too, one head of cabbage is like three bucks and it feeds you longer than a bag of frozen stuff that costs twice as much.