Big tech products made to make you happy. How did that happen?

Commercial product/service/app can be offered for free but it wouldn’t be sustainable if the money wasn’t made in some way or the other. Infrastructure, employees, real estate, etc., all have some cost to it, but in some strange unclear way, most non-tech users magically believe in good will of service provider (with few truly extraordinary exceptions).

So how was this magical thinking instilled in regular, non-tech people? And why is it not being questioned at all?