I may be misunderstanding, but it looks like the micro-services comparison here is based on very high usage. Another use for micro-services, like lambda, is exactly the opposite. If you have very low usage, you aren't paying for cycles you don't use the way you would be if you either owned the machine, or rented it from AWS or DO and left it on all the time (which you'd have to do in order to serve that randomly-arriving one hit per day!)