Sorry for the late reply but it's Monday and I don't feel like doing actual work yet and lol, just lol if you read HN when you're not on the clock.
Much like taxes, it comes down to market access. By accepting credit cards, they get access to a larger market, a larger potential set of customers. The cashless person can patronize their business thanks to the electronic payment infrastructure the banks created and maintain. That infrastructure is paid for by transaction fees.
If a business owner feels that cards are too much of a privacy issue or whatever aside from the fees, that's their opinion and they're welcome to it. They can work to find payment systems and markets that align with their values if it bugs them sufficiently. There is a possibility that the intersection of the sets of "places where the markets align with their values", "places where the business owner wants to operate", and "places where the business can be successful" might be small or nonexistent. You can't always get what you want, as the song says.
Likewise, a business owner who feels taxes are unfair can look for places where the taxes align to their values. There may or may not be places that have an agreeable tax structure and sufficient markets to sustain the business.
I get pretty tired of business owners who act like the government and service providers are unjustly stealing from them when often the business' entire ability to exist and sustain itself depends on the infrastructure and services provided.
You're the messenger, yes, but no one forced you to put your hands on the keyboard. Don't be surprised if you're handed a response for the message you chose to deliver. Feel free to carry it back to the business owners you've chatted with.