who to pay

reading a news report.
a woman, with 2 kids, remarried. nothing unusual right...

but she divorced the second marriage. the kids follow the mother. nothing wrong also, as she is their natural mother.

here's the twist.

the mother requested for allowance for herself and her 2 kids.
well, nothing wrong except the kids are not the father's.
i meant he's not their father, only stepfather. Y should he pay for their maintenance?

By law, once if they (the adults) are remarried, the father accepts that the kids are also his.

But in a guy's point of view, why should i pay for the kids' maintenance? funny right?