Companies do this all the time. They'll negotiate for very favorable payment terms from suppliers and then tighten the payment terms for customers. For example: They'll pay suppliers in 60 days and receive payment from customers in 30. The result? If they turn around product quickly, they can use the cash from customers to pay the suppliers, using none of their own money.
Can individuals do the same?
Sure. Keeping an eye on when my credit card cuts, I can buy a product and have 30 days to pay for it without incurring interest charges. During that time, I could sell the product for a profit.
I'm doing this currently with my book sales (authors only get a certain number of free books, my number is 5, after that, I have to buy ). I buy the eBook on my credit card and collect the cash from readers immediately (right now, I'm reinvesting that cash in more book purchases but I could invest it elsewhere).
What if you're not flipping the purchase? Well, if you're like me and don't buy unless you have cash to pay for it, you can still invest the cash for the month, getting your little bit in interest (little bits add up), and pay at the end of the month.
Cash flow counts. The longer you can extend the interest free period of payments and the sooner you receive the cash, the better (that is why many stores offer a cash "discount", they're working the float).