This almost sounds like mixing up the terms or history of open source and free software.
While both may have been driven by ideals, many of the licenses typically applied by people who call themselves "open source developers" do not contain copyleft. Therefore it is inherently easy for corporations to "steal" the code. "Steal" in quotes, because when the developers chose a license, they should have been aware of that their software can be used in any context without they themselves ever learning about it or seeing any contributions flowing back, so it is not really stealing anything, but the developers short-sighted choice of license.
Sustainability in terms of keeping things open (libre) is more an area of licenses like GPL, AGPL, which contain copyleft. These are more commonly applied by developers calling themselves "free software developers". Most self-respecting free software developers will also call their software free (libre) software, instead of saying open source, even, if many open source licenses are also valid free software licenses.