You still had to put a downpayment that didn't go somewhere else for the whole length of your mortgage.
Also, if your rent covers your mortgage, I will assume that you were simply lucky enough that in your particular area the housing market rose more rapidly than in others (for example the bay area). But you didn't know this in advance and it could very well have gone the other way around.
Me? Oh, no my only payments were about $3,000 in the closing costs. I did NOT have to put down a sizable down payment because I got an FHA backed loan.
You still had to put a downpayment that didn't go somewhere else for the whole length of your mortgage.
Also, if your rent covers your mortgage, I will assume that you were simply lucky enough that in your particular area the housing market rose more rapidly than in others (for example the bay area). But you didn't know this in advance and it could very well have gone the other way around.