The consequences is that these companies get very rich and they eventually take-over the open-source project.

See Redis for example, two Israeli dudes took the open-source Redis, made tons of money.

Everyone is happy: the two founders became rich, the VCs became rich.

What about the authors and contributors of Redis ? Well thank you for the gift. As a present you can have the privilege to work for us to keep maintaining your bugs. Don't complain too much.

Then you can rewrite the history to make it sound like you created Redis and it's a win, while it's actually just a very smart dude in Italy who wrote most of the software using his own sweat and support from his employer (Pivotal).