I've always wondered why I can't pay some small fee (20 cents? $1?) to read an article. Why it have to be an entire subscription? If I put $20 / month into an account and then spend that bit by bit on high quality articles from different sites I'd gladly do that.
The math doesn’t work out:
https://www.cjr.org/opinion/micropayments-subscription-pay-b...
because payment processors hate small payments and punish accordingly (with flat fee +%)
It would be cheaper for you but not very profitable for them.
1. You can be sure that most people still won't pay to read the article, so it might not be worth doing at all
2. "Number of subscribers" is a real, meaningful metric used across the industry for various purposes, including informing advertisers and calculating recurring revenue. Your proposal, on the other hand, is somewhat odd and questionable that people probably don't know how to make use of.