[beepbooptheory]

Why? Is there something different in your mind that startups like these tend to do?

It seems to me that in the freemarket you can either create a "need", broadly construed, or facilitate access to a need that already exists. What else is there?

[oneplane]

Efficiency, specialisation, scale. You doing one thing on your own vs. a collection of many of those 'things' you used to do solo, guess which one has more potential?

This does or course not mean that this applies all the time, everywhere, forever. But in this case, the 'startup' merely has a model of economy of scale, and then probably making sure the benefits are big enough that they can scrape a bit of a provision off of it. That way they can make money while still delivering something that has a higher value to a customer than the customer doing it themselves.