It has become nearly a standard where large multi-billion companies are throwing money at hundreds of projects that show a bit of promise, it's the only way right now to keep up with every trend in the world as your own company can't go on a developer hiring spree to cover every niche, so you just invest in each and hope you nailed it as of course, not every bet will bring a profit, and some will fail miserably.
Precisely, it's really just them hedging possibilities. The same reason how some companies tend to invest in their competitors; just so they end up getting some competitor equity when it's the case that their competitor totally kills their business.