Frankly, that’s the reason – the original reason, and the most important – to use Free Software. With very few exceptions, the origin story of every Free Software project was somebody getting fed up with a piece of proprietary software either abusing them or just not doing what they wanted it to do. In fact, the entire Free Software movement itself was invented in the first place because Richard Stallman got fed up with Xerox’s bullshit back in the day!
So yeah, there you go: that’s the only reason you need, and you already knew it.