It is more about gauging public sentiment. If Prop F passed Expedia would have been wise to reconsider the deal. The last thing you want to do is spend all that money into an industry headed for heavy regulation that was voted in by citizens.
You act like prop F was a national proposition or somehow international, this was just one city. Even if prop F passed it would not bring airbnb down as they operate in 34k+ cities around the world. Expedia is also targeting the int'l market. I doubt they would reconsider just over SF.
