@jackfruitburger - I am sorry that I didn’t make it clear in my earlier post, but I DO think your dh is being unreasonable in his unwillingness to compromise.
For me, the best compromise would come from the two of you looking at the budget and, as I said earlier, setting aside the money for the essential bills, then setting a budget dividing up the rest between household food shop, individual allowances and family fun, and then see if you can adjust those a bit to set up a regular amount into savings - some of which could be your buffer if interest rates go up, and some of which could be towards a family holiday - that bit could come from the family fun budget.
But of course this will only work if both partners agree to it and are willing to stick to it, and it doesn’t sound as if your dh would.
Might it be worth suggesting a week’s trial of different packed lunch options for him - using wraps or crusty rolls rather than sliced bread, and some nice fillings that won’t make it soggy, to show him he can have nice lunches without breaking the bank. I might even be tempted to make chorizo sausage rolls for him - a whole ring of chorizo is £2, and if it was chopped up and mixed with ordinary sausage meat, and made into big sausage rolls with ready rolled pastry then baked and frozen, he could have his favourite lunch at a fraction of the cost of the bought ones.
Or maybe buy good sausage rolls from the supermarket - Tesco finest do a pack of 4 really delicious ones - either hog roast, or sausage and cheddar - at about half the price of the one he is buying.
Sorry if this is all stuff you have already thought of - and I do realise that most of what I suggested involves extra effort for you - but if you show him it is a) possible, b) still nice and c) easy, he would have no excuse not to take it over in the longer term.