Not true. There are many ways a PPL can make money with a plane. They can sell minnows, take pictures, stake mineral claims, ag flying, etc. What they can't do is fly passengers or cargo for remuneration (with the exceptions listed in the CARs).
There is a company without an AOC that has been operating for years with a fleet of Cessna 150's that flies around taking pictures of farms and then the sales people go door to door trying to sell them. Another one goes and collects minnows and then delivers them to the lodges and sells them there. On the other hand, if the company sold the minnows and then went and delivered cargo, that would not be legal.