The question is whether or not the brunch will be well-attended or not. If it is, regardless of the dissent in this thread, then Disney gets the message that it was well-priced.
I don't care about this particular brunch, but I know that I place a specific value on attending an event which is priced so high that young children are less likely to be in evidence. For example, we subscribe to a local theater, and specifically for Saturday night, when the prices rival the downtown Boston theater prices. Unremarkably, more shows go off without disturbance from children, than when we subscribed to a lower-priced performance time. It is definitely worth the extra money.