[criley]

It is possible to block the installation of Chrome extensions through group policy.

http://www.chromium.org/administrators/policy-list-3

You can whitelist and blacklist extensions, whitelist sources, force install extensions and block them by type only.

It shouldn't be hard to prevent all extensions from running.

[mustpax]

It is downright scary how incompetent, indifferent and arrogant most IT organizations are. They are usually run by someone who's background is in procurement (i.e. buying things cheap) or compliance (i.e. lawyer). And if you try to explain something like this to them, they just DO NOT CARE.