Morality aside, the logistics of this means you cannot literally PayPal someone 10 cents. The processing cost isn't worth transferring such a small amount.
So the answer to this is to pay $5 and be able to see 50 replies. But what if you're unsure you want to even see that many replies? It's now a steep cost to consider.
I suspect they want to do a side-channel payment system.
So you pay X $100 or w/e and they increase your account by 96.50 or w/e it is after fees and X pocket that 96.50 into X's own bank account. Then when you have to pay 10 cents to somebody they move 10 cents in X's ledger while the 96.50 never moves between bank accounts.
Eventually whoever's article you read (Y) will want to withdrawal what the ledger has but ideally at that point it will be a higher value like $100 so they'd get $96.50 of that but individually each reader only paid 10 cents.
So the answer to this is to pay $5 and be able to see 50 replies. But what if you're unsure you want to even see that many replies? It's now a steep cost to consider.