Instead of keeping something just in case, think of the thrift store as a rent-free storage unit with a tiny pay-per-use fee. Keep only what you need, and enjoy a clutter-free life. Hmmm, I knew there was a reason I loved thrift stores.
There is actually an area close to where I live that has different storage units like these. I have never actually stored anything in a unit before. However, I can see how it could possibly be a viable solution depending on the situation.