At a minimum, one could switch cell phone billing so that only the caller pays, not the recipient.
Are there any countries besides the US that charge the callee? It's completely unheard of in Europe.
I did spend some time in the US about ten years ago, and I do remember being very surprised at being charged for calls received, and even for texts received, although you have no influence on accepting them! Such a weird system.
Or, if you phoned a store to ask whether they stocked an item you want to buy, do you think the store would press the button?
At any rate, people already (often) pay to make phone calls. By dealing a number, you're implicitly agreeing to pay. Just think of it as a charge (often waived) for the time of the person answering it.