Same here and I'm trying to use them up so I don't lose or forget about them. But half the time I just end up buying things elsewhere with cash (well credit card that's used for everything for the points, then paid off each month). It's not like I don't buy 'treats' because I do, but I need to want something, then buy it. I don't look and think 'I have money available, what can I spend it on' like your DH seems to be suggesting.
Off the top of my head, I have:
Some Amazon vouchers from a birthday gift - I spent about half of them on a thing, have used a bit on 99 p kindle books, the rest just sits there and will probably go the same way.
About £50 in M&S vouchers, taken from Quidco because you get a bit more than cash. I'll probably use these for food shopping TBH.
Enough McDonalds points for a meal deal.
About £60 of Nectar points. I'm in a Mexican stand off with them because I used to use my Nectar points in the double up event to buy fizzy wine just before Christmas but they seem to have stopped doing that, but I know that if I use the points for something else, they'll bring it back, so I'm currently waiting it out.
A £20 Currys voucher as a freebie for signing up to ID mobile. But we need a new fridge so likely use it when we buy that.
About £30 as Natwest current account cashback
A tiny amount of Clubcard and Boots points, but I hardly ever shop at either of these so never amounts to much. Tesco once sent me a Christmas card/voucher which made a big thing about 'here are your points, treat yourself for Christmas' and I got a whole £1.50, which probably wouldn't have bought a box of mince pies.
Probably about a tenner of Zooplus points, which I tend to use to get free Dreamies just before they're about to run out.