Dan, thanks. I wanted to make sure I wasn't missing some term. As you know, many of the terms get covered both in the main P&S agreement and an addendum, and it's nice to have more ammunition for these types of situations.
Fortunately these types of situations are relatively rare. We've only had a couple such situations, and one of them was with one of our seller clients who had been very reliable up to closing. As it was it took him an extra 12 hours to get his stuff moved out, so that wasn't as horrible as what Ron describes. I've seen many places where I was worried about having all the stuff removed where it was actually removed on time.
I probably should add that before throwing stuff away it would be prudent to have an attorney review the contract.