The peanut butter example might be overly simplistic, especially because it compares b2c to b2b, but other than that the original point is actually correct. In B2B it's very common to order things before they are manufactured. If a company orders 100 new company cars, it's very rare that the car dealership (or even the car manufacturer) has all 100 of them on their yard, ready to be taken away. Especially when you are talking about large-scale b2b purchasing, it's very common that orders are taken months or even years in advance. And here we aren't even talking about regular "my company needs to buy 100 RAM sticks to upgrade the laptops", but we are talking about manufacturing deals. They always order stuff like RAM chips way in advance, even if only to secure reliable and predictable pricing and availability.