In my experience, all ways to 'avoid knowing what you're doing' are expensive.
It's all about time, and lack of it. If you can spend 1/10th of the time and still make a good profit, you could spend the other 9/10ths doing other profitable things.
At the end of the day, you're still going to need to A) learn what you're doing or B) hire someone who does know what they're doing - and given that one of the major selling points of these PaaS offerings is that you can get up and running without needing a dedicated sys admin, this seems particularly silly to me!
