If you want to get wound up about manuals. The CAR, CAO and ops manual also contains a few paragraphs giving the captain a fair bit of discretionary latitude
However the ops manual takes precedence over all those things. I'm not saying I agree with the light policy, it's daft, I'm just saying that's the way it is. If you want a tricky issue have a look at the jumpseat policy. The CAR says one thing the ops manuals another.
Tea and bickies? For turning off wing lights?
As a isolated incident probably not. However after maybe a few minor issues before that it could be used as an excuse for a meeting. I have certainly heard of worse reasons for being pulled in.