.You're behaving like customer service is some sort of calling from above where only people who are completely selfless and self effacing need apply. That's bollocks. Customer facing staff are there to facilitate a transaction between someone getting goods or a service they want or need and the company selling it, not to boost people's ego's, not to make them feel like a saint for paying for those goods or that service, and not to provide endless adoration and attention to anyone and everyone.
People work in those jobs for the same reason they work in just about any job, they need the wages to survive. Not because they've been called from God to serve you a pint of milk like a subservient apostle, give you validation and boost your ego. If anyone needs an 'experience' above actually getting their pint of milk, paying for it and manners while that happens but needs subservience and deference while getting it, they're the one with the problem.
You're right that fining people £1000 if a customer decides that they've been treated unreasonably will change customer service, I for one will be out the door and so would just about everyone else, because I'm not risking my financial stability on the whim of someone else who can decide unreasonably and unfairly to take almost a months wages from me because they've got a chip on their shoulder and thinks they should be able to take that out on me because I'm 'less' than them.
Customer service staff aren't responsible for the ills of the world as you see them, they're not responsible for other people's behaviour, they're not responsible for the commercialisation of everything and anything, in a bid to make other people rich. You're handing the people who are responsible the perfect whipping boy to blame everything on and take the concequences, and apparently want to now financially punish them for the pleasure.
A lot of the issues that exist are down to lack of staffing, because the role of anyone who serves anyone else is seen as less than by society and less and less people are taking the 'opportunity' to be treated like that.
Without staff, places collapse just as much as without customers, it's a two way street, no staff means no service and unreasonable and unrealistic expectations contribute towards less staff and poorer service.
And if you find a policy doesn't work for you, then no amount of me believing in it is going to change that, me believing in it isn't going to make it magically work for you, that's just a way to excuse people who want to be rude, aggressive or abusive towards another person because they know they can be.