There is no "General Public." Trying to reach or mobilize the general public will fail by definition, because the general public does not exist.  When someone uses the phrase, they don't mean everyone – otherwise, they would say "everyone," which includes infants, the President, and the mentally ill.

Think about how people usually characterize the general public: apathetic, uninformed, easily led, too busy with their own lives to pay attention to important issues.   Rarely does a speaker mean to include themselves when they speak of the general public.  Usually, "the general public" means Them – not Us.  Unless, of course, it's used to mean Us – not Them, as in "the general public does not support their extreme ideas." 

There are times when the use of "the general public" isn't intended to be divisive; sometimes it's just lazy. A grant proposal might say, "Our project is designed to raise awareness of farmers, small business owners, teachers, students and the general public." "The general public" stands in to mean everyone else we can't think of.