"It is possible but we expect not to do" view does not make me feel comfort. If there is an open risk this must be handled. Most of the extentions are from third-parties on chrome and i use tens of them. Who has the time to control what it does everytime before the installation, and also after every update? Extentions are very usefull feature that make life easier and make people prefer chrome. I believe it would be annoying if we can't use them safely.