Yes this issue with not being able to change the vanity URL on FB is really going to bite many companies. Take for example the Japanese Tourism Organisation that went with "visitjapan2010". They already have many people asking where the 2011 page is! The number of new fans has dropped off.
The real problem at the end of the day is FB arrogant attitude. Reminds me of Yahoo! eight years ago and look where they are now. FB thinks it's the next Google, but the reality is far from it. People don't go to FB to shop or to find a place to buy or book, they go to Google.
How many businesses do you know that are getting a good return on their investment in their FB advertising/campaigns? I haven't found one yet.