Yes, we DO expect you to read a group before posting to it. It is an ancient element of netiquette that someone should read a group long enough to learn its ways before posting in that group. And yes, I know my bincancel notices sometimes violate this standard. I don't complain when a 'bot cancels them for violating a rule I was unaware of.
Ignorance is no excuse.
The strictest standards apply. If that were not the case, local and regional groups wouldn't stand a chance. I hope this helps.