you realize that if you contribute to a company apache project without a CLA, they can change the license out from under you to _any_ license that they want, right?
The way I've understood it is part of the point of CLA's is to allow license changes, and that without them no license changes are possible to community projects. Because all the contributors own the copyright to the code they contributed, which they licensed under the existing license. To change the license you'd need to contact all the contributors and get permission (so okay, not impossible, just infeasible). The CLA is getting that permission in advance, to let some controlling body change copyright later.
I thought the point of CLA's in general is to stop contributors from revoking their license, or claiming the entire program is a collaborative work and that they have joint copyright over all of it. I don't think either has ever happened in open source, but I believe is possible, at least in the US.
[note: am co-founder/ceo of grafana labs]