I have myriad issues with the personal ethics of the owners of Chick-fil-A - but their model does make sense to me.

They're clearly not just wanting to sell their brand - they're wanting to own their brand.

The 10k is just a token - It's maybe more than you have in your clearing account, but a figure that most people could likely produce and is just an indicator that "you're serious"

Important part is that they put you through the grinder to make sure you're the person they want to run their store. To be honest just looks like a regular job interview - with the exception that they charge you to join the company, but you get a cut of the profits.

Not even sure if they're in the UK yet, but you can see the converse with Subway that keeps appearing all over the place, despite not having any customers.