And once that happens, voting with your feet won't even be an option
Yes it will. there are alternative finance systems available.
I know of one group who co-ops. Everyone who is part of the group puts in a figure each month and every month a different (rotating) member of the co-op receives the funds. This works great for small things such as car finance because it is interest free and profit free.
There are Islamic finance options with lend-lease schemes and rent to own schemes where your rent is paying your mortgage.
Barter groups etc.
If enough people voted with their feet the banks would be forced to make changes but I think that one of the issues that we need to overcome is people's sense of powerlessness and the idea that your 'vote' doesn't count.

As for the main topic - ****ing disgraceful and if my bank did follow suite I would not hesitate to remove my personal and business banking from them.