Why do people use obvious spyware when free software exists?
Yes, why do people use products from Microsoft, Apple, Google, Amazon, ...
I work at Apple, so I’m not concerned about being monitored—it’s all company-owned equipment and data anyway.
It was the same when I worked at Microsoft. I used Microsoft products exclusively, regardless of any potential privacy concerns.
Employees at Google and Amazon do the same. It’s known as “dogfooding”—using your own products to test and improve them (https://en.wikipedia.org/wiki/Eating_your_own_dog_food).
As for why people outside these companies use their products, it usually comes down to two reasons: a) Their employer has purchased licenses and wants employees to use them, either for compliance or to get value from the investment; or b) They genuinely like the product—whether it’s because of its features, price, performance, support, or overall experience.