If I understand your question as referring to people who have mortgages and rent out their properties to pay their mortgages, then in a non-legal way, they kind of are - I say 'kind of' as the renter doesn't end up owning anything in the end.
I myself am renting at the moment. I've deliberately chosen to rent from people that own and to not have a mortgage. However and ultimately, most all money that exists today in many many countries - I don't know the numbers, but from my research I only know of a few examples where it's not created as debt, as such once the banks slow there lending, as they have world wide since Basel II regulations came into effect at the end of 2008 (yes, that does correspond to the start of the global economic slide), then the amount of currency in circulation declines as the mortgage payers drain the economy of money.
I bring that point up, because in a way, as long as you are using Federal Reserve notes as money (or many of a myriad of other national currencies), then you are taking part in a system of nefarious lending and ultimately (and ultimately is a day coming very soon) there will be very little money in the 'common' economy and heaps and heaps in the casino-style economy of high finance. This will cause rampant inflation in the value of imported goods - of which the US citizenry has become very dependent. What has functionally taken place since the institution of the Federal Reserve Bank of the US in 1913 is the complete looting of the wealth of the real US 'common' economy with the rubber stamp of the congress and the direct knowledge and understanding of all of the recent presidential administrations - if not all of them since the inception of the Fed.
The recent US government bailouts of the main banks are really one of the last big thefts as such money will not go back into the real common economy via the making of new loans, thanks to Basel II. Instead the money is being spent to buy up and consolidate various assets (real wealth) that remains outside of the control of the top banks. While some of this money will make it's way back into the common economy very very little via the fractional reserve mechanisms that create vast amounts new credit.
If I've completely missed the point of your question, I do apologize. . .I do have a tendency to go on a bit
