When BF and I stay over it's usually at mine, for various logistical reasons. When he stays here I will have food and drink in that I'm happy to share with him. I don't particularly shop specially, but I cook daily for myself and will do enough for two when he's here and there's always bread/milk etc in.
BF thinks meal to meal, so he'll go to the shop (or takeaway) when he's hungry.
I stayed at his last night. A long planned thing, and he'd seemed excited that I'd be staying at his for a change. We'd eaten out last night, but at breakfast he literally had nothing to offer me. He was going to do beans on toast but there was no bread...
I can't imagine having any guest, let alone one who does so much or me, and not thinking ahead to what they'll have for breakfast, but then I guess this is the way he lives himself, there was nothing for him either.
Fwiw he does contribute to cost of food when he's at mine and will sometimes bring something.