It is not just, people keep giving their money to them.
Problem is that most common people always value a convenient prison over a little less convenient freedom. Most common people can't deal with freedom and need a hand of their favorite overlord to function. It is not a conscious decision as if you ask them they will reject that thought.
But the products created by these giants are in fact often better than their smaller competitors, even if for no better reason than because the large company is subsiding the construction. The narrative assumption that people want the bad parts of these companies ignores the survey data that shows that people do care about things like privacy, and choose options when possible that optimize for it... they just can't afford it or have to make tradeoffs against it versus other things; like, I would never leave Facebook as I have lots of friends who use it and I want to see their photos and hear about their lives and get invited to their parties. A remarkable number of people--despite all the pains and costs of doing so--jailbroke their iPhones: most people like what Apple is selling despite it being closed, not because of it.
Do you mind my asking what survey data this is? I would like it to be true, but my everyday experiences with people continually suggests otherwise. You just have to look at the example you give, Facebook, to see how much data people willingly put online in the public domain. This isn't because they wish they could share privately with a small number of people and have had to compromise - it's because they relish the act of publishing to a virtually infinite audience.
Isnt most of their profit cloud services to businesses?