I don't want to start a big debate as you clearly have a different approach to business, perhaps it varies from country to country. Where I'm from your logic does not work for over a decade now. It's all about demand, quality and reliability now. If there were a different dev selling for 30% cheaper I wouldn't trust it because I don't know if he's going to be reliable.
Business is not about who offers better or who is cheaper. Business is about delivering something people want. If you want an iPhone, you will pay 5 times more for it than for an Android even tho they are technically the same phones. But no one makes another iPhone and they have their unique features, and there are lots of Androids. Iphone has no competition so they have their prices high.
Let's say for a second that there are 2 Devs like IGCNs then perhaps your logic would apply and they would fight for the customers by lowering the price or offering something more. But there isn't.
And if there isn't, we have to either accept their conditions or stop doing what we are doing. I get it, I don't want to spend extra money every month or so but It's not unfair it's just business. It's perhaps better for them to get higher payment from 500 users and lose 10% of the customers by doing it, you will never know, but that is their business.
But thats just my opinion 🙄