People commit theft because the barriers / consequences of theft to obtain an item or less than the barriers/consequences of legitimate purchase. It's always a supply and availability issue. Humans aren't intrinsically evil. Also there aren't a bunch of programs to provide free baby supplies. Even WIC requires application but some people might not have the time or ability to go to. And it's not free with WIC, you still have to pay.
Also if you want to talk philosophy, children are too young to consent and be beholden to the social contract. They're participation is mandatory because they are innocent and dependent. It's our obligation to provide for them collectively.
Look, I get it that it's cool to rag on a company for being cheap and short sighted but this toilet paper is not bought to save money. They know you use more. It's bought because thin toilet paper breaks down quickly in water, meaning rather than needing a plumber to wrestle your turd nest out of the pipes with a snake, they can hang an out of order sign on the stall for a shift and try flushing again once the "toilet paper" has completely dissolved.