I personally think the CMs do a wonderful job providing information. I cannot tell you how many times I've seen guests misunderstand what CMs (and folks here on the DIS, for that matter) have explained perfectly well. I know some folks won't want to read this, but sometimes guests just hear what they want to hear, believe what they want to believe, without regard to the reality of the situation.
Regarding CMs knowing more than us -- no way. We spend our leisure time studying, learning, fixating on this place. For mos of the CMs, it's just a job. If you ask the CM at Le Cellier about Le Cellier's policy, that's one thing, but I see folks asking reservations CMs intensely detailed questions about specific restaurant policy, or asking hotel front desk clerks intensely detailed questions about ride operations. It's mind-blowing, sometimes. The CMs do the best they can, I believe. If they make an error, I believe, it is in not saying, "I don't know," as often as they should. I think the expectation that all 50,000 WDW employees know what each and every other of the 50,000 employees know is insanity.