Shariah Compliant Banking At UK's Lloyd's TSB

Had no idea that Lloyd's TSB bank has a Shariah compliant full service banking system. They have for almost 10 years.  It started at a few branches in the U.K. in 2005 and then went nationwide in 2006. They offer everything from business to personal accounts to mortgage accounts.  Interest free on all accounts, and no minimum amount in the 'current accounts'.  Apparently, with mortgages, the bank purchases the house and they get to pay off the purchase price in monthly installments. Ownership is transferred once the purchase price has been paid.

My question.  What do the banks get out of this?

H/T Photo EDL F/B Page