Yes I do - consciously - and I find it incredibly revolutionary.
I think Marie Kondo was the first one to make me reconsider this - she says rather than keeping the item, why not see shops as being a giant storage unit, with an incredibly cheap price. DH illustrated this to me brilliantly a few months later when I complained about all the cables he was keeping. He went to Ikea, and bought a big plastic tub for €20 to keep them in. We do occasionally look through that tub for a cable, but the vast majority of the cables in that tub, we could replace for less than €5 on amazon. It is very rare that we actually go searching for a cable in that tub. It just lived on top of the kids' wardrobe, collecting dust, until we moved and now it is in a storage cupboard. We could have saved the €20, gained the space used by that big tub and not had the heavy thing which is hard to move and clean around, and replaced a cable 4x (which is certainly more often than we have used any cables from that tub in the last 7 years since he bought it).
The way she frames it is that the amount of money you would spend on a storage unit, or on higher rent/mortgage for a bigger house, is much more than the cost of replacing items when you need them later, rather than taking up so much (collective) space with things that you "might" use later.
Then secondly, Dana K White was another which made me reconsider this with her question, which I find genius - she says when tidying up - "If you wanted one of these, where in your house would you look for it first?" Then if you can't answer the question she says think realistically, whether you can't answer because it would never occur to you to look for this item in your house. This last one is SO true for me. I would keep a load of random scraps of ribbon, thinking it would be useful for crafts or presents or something. And then when I wanted to wrap a present or do a craft using ribbon, I would go to a shop and buy ribbon. It would never even occur to me to go looking for the other ribbons I had saved!
Or, I'd look for things (sellotape, batteries, whatever) and not be able to find them anywhere and end up having to re-buy them anyway.
So I think I was actually re-buying stuff much more often when the house was more cluttered, because I didn't know what I had.
The even bigger "level up" I found for this is that I re-bought some childhood books which I have no idea where they ended up but I didn't have them. So I bought new copies to read to the DC. I found that the nostalgia, the memories, were all there just the same. It didn't matter at all that it wasn't the exact copy that I had once owned myself. It literally didn't matter! I realised that everything I was holding onto from DS1 in case DS2 might want it (there is a ten year gap between them) I could let go of. Some things I sold, some I just gave away or donated, or threw away if it was trashed, but anything I wanted I could probably rebuy. If it isn't made any more, I can get a newer version, or look second hand.
Sometimes I do buy stuff that we used to have, and it's usually better - because it's in newer condition and hasn't been degrading quietly in a cupboard for years. I also feel confident in spending the money on the item, because I know that it will be something we will use and enjoy, rather than when you buy something you've never used before and don't know if it is really any good.
Obviously there are sentimental items which I still do keep, or things which would be difficult or expensive to replace, (though sometimes even expensive things are worth selling and then buying second hand later) but I am much less anxious about letting things go which we don't need at this moment, knowing that it will be highly likely I can get hold of another one in the future if I especially want to.