When I buy something, even if it's from a thrift shop, I've spent time looking for it and money to purchase it. I've learned to pay cash instead of using credit so that I'm not paying the hidden cost of interest on it as well. Even if it was free from Freecycle, it cost me time to read the listings and time and money for gasoline to pick it up.
I pay rent to house the item while it lives with me, I also need to pay to move it when I move, some people pay a cleaning person to keep it dusted, buy a security system to make sure that no one steals it, and some of us fall for the idea that if it feels crowded in our home that it's a good idea to pay rent to hide things in a storage facility. (Ug, don't do it!!!)
When does the time and money suck stop when it comes to the things we own?
Certainly not when we want to get rid of it. This requires research to see what can I sell it for, renting a van to move it out of storage so that I can sell it easier, time to write the blurb to put onto Craigslist or Ebay, time to meet with people to see if they are interested in buying it, and on and on.
I definitely plan on buying less in the future.