Aside from Murray being the much better player there are a few reasons
1. He has been in great form for months
2. Murray is extremely difficult to beat in London. He basically only loses to fed and novak at home. The crowd will be very pro murray
3. Winning the last 4 in h2h has effects on mentally weak at times ferrer
4. Most importantly, the back door win - Murray stated in the news that he has been preparing for the davis cup final and the switch to the world tour final surface effects his back. You are probably thinking well isn't that a bad thing? He is basically claiming that if he has "back" trouble he will retire. Knowing Andy Murray, if he loses the first set he will retire and we get a push, if he wins the first set, then we have andy murray at home at like -5000 fav or something redic. Murray is an injury drama queen and will have no problem retiring a week before the davis cup finals.
http://www.bbc.com/sport/tennis/34826428
Murray interview ^^
I think there is a very good chance we are free rolling here if he loses the first set. I highly suggest betting on a site that requires a full match to be played if you go large.