I think it makes sense because someone can start an operation with few clients and limit infrastructure costs. As the number of clients grows, you can improve y

I think it makes sense because someone can start an operation with few clients and limit infrastructure costs. As the number of clients grows, you can improve your infrastructure. By the time you get to thousands of customers, you can switch to bare-metal servers and dramatically improve your bottom line. In other words, you don't need a big machine, expensive colocation, upfront bandwidth costs, just to serve two clients.