Read the following paragraph:

"Have you ever noticed that all that advice the smart people give you for saving money only works if you already have money? They tell you never to pay for a bank account, but free banking doesn’t come cheap. You can’t get free checking without a minimum balance. You can’t get a no-fee student savings account when you can’t afford tuition. They tell you that buying in bulk is cheaper in the long run, but bigger sizes cost more right now. A lower price per each doesn’t matter if you don’t have enough cash in your wallet for the economy size. And when it comes to necessities like toilet paper and diapers, you can’t wait for them to go on sale, either."
Which sentence below is a major supporting detail of the reading?