First, micropayments are less than a penny (the "micro" part). Anything 25 cents is just a payment.
Second, 25 cents means I can quickly bump into my monthly/yearly maximums and have to start cutting back on my reading each month and year end. I don't want to go each October-December without being able to read the web just because I overspent on marginal articles earlier in the year.
The model that will work (for me anyway) is one like Netflix. I pay essentially a yearly fee and can consume as much as I want. Bingeing, if you will, when I desire. But only if, again like Netflix, a significant portion of the web is included. If I have to pay for five or six subscriptions it's a no-go because it gets too expensive.