I'm probably projecting the idea I have of myself here but if someone says

> every exchange is about what's best for humanity and the public in general

it means that they are the kind of individual who deeply care for things to work, relationships to be good and fruitful and thus if they made someone pay for something, they think they must listen to them and comply their requests, because well, they are a paying customer and the customer is always right, they gave me their money etc etc

There is no tension there.

You can care about the work and your customer will still setting healthy boundaries and accepting that wanting to do good work for them doesn't mean you are beside them.

Business is fundamentally about partnership, transactional and moneyed partnerships, but partnership still. It's best when both suppliers and customers are aware of that and like any partnership, it structured and can be stopped by both partners. You don't technically owe them more than what's in the contract and that puts a hard stop which is easy to identify if needed.