It's not about people not wanting to pay, it's that the value of a single article is too small to charge money for. A single article is maybe worth a hundredth of a cent to me. There's no viable mechanism for me to pay a hundredth of a cent to a writer, just transaction fees will be more than the amount transacted.
I'm not going to pay a subscription to a site I might not ever visit again. I'm also not going to pay a subscription fee to every site I come across that might have a decently written article once in a while. Advertising ends up being the only viable way to "charge" a tiny fraction of a cent to readers.