Add Leverage (Mortgage) and you greatly increase the ROI especially from the perspective of using Rents (other peoples money) to pay down the mortgage and increase your equity in the property over time. At this point then yes price appreciation is secondary bonus and we have an arguement of how and why Real Estate can be better than Growth Stocks in some scenarios and for some investors.
I have only dabbled in drop-shipping before when I had an eCommerce platform 6 years ago or so. I think it is something that you could do on the side, but you would want to do in depth research on the industry you want to get into before setting up shop. It may be a little less passive up front, but over time you could take your hands off the wheel.