I saw a couple of my favorites close in the past few years: one in SF,where the landlord was going to raise the rent by an outrageous amount and the shop owner said her life ran in 12 year cycles, that she had been open 12 years, and now it was time to move on.
Another one was in Auburn, CA, and the owners wanted to retire. I don't think anyone came to buy it. It had been one of the shops in a Quilt Sampler Best Shops issue. Just checked and they are now an online only shop.