Having done most of the steps you mention above for multile clients, I'd contend the time overhead is not very large - most things can be automated, and once that is done an extra instance is just a matter of spinning up a server and deploying - also you can scale a very long way on one or two instances when the hardware is beefy enough (e.g. this website), backup, deploy, testing can all be automated. There are definitely some situations where a service like Heroku or AWS makes a lot of sense, but it can get expensive very quickly; you're trading time to setup/manage for higher ongoing costs forever. VPS is cheaper but requires some setup. That's a trade-off each company has to evaluate individually given the talent and money they have.