When we were younger, I used to buy a whole lot more used items -- but that was before we had a fully furnished house. In those days, we needed to buy furniture, kitchen items, and so forth, and they were easy to find used. Then we had the kids, and it only made sense to buy their quickly-outgrown clothing used.
Fast forward to today, we don't buy all that much. Our house is furnished, and we aren't the type of people to re-do the living room because a new color has come into fashion. Our closets are full of clothes, and we buy only a few items each year (sometimes new, sometimes used) so our wardrobes will stay functional. We don't need new appliances, etc. on a regular basis. When we do buy something, we investigate our options carefully and "buy smart", regardless of whether that's new or used.