Google ran a huge push to get these into schools too.. There was a LOT of pressure on Schools to adopt from various partners (or at least that happened in the UK)...
Google is aware of the Microsoft gains from getting people used to their products at a young age...
I help maintain Etherpad and this cuts so deep.
The main counter-argument I have is restrictive installation policies especially in Edu/bluechip IE you can do whatever the fuck you want in the sandbox that is your web browser but if you want to install some software you have to wait 4 weeks for approval then another 4 weeks to get approval for each update.
Also security updates/patches for native applications can be really shitty especially on Microsoft inflicted devices.. For example, if you want to update Inkscape on Windows you have to do a whole download/install process. This can lead to security related issues..