Why did the anti federalists believe the constitution was a class based document?

Most likely because it was just the anti-federalists and the federalists discussing everything such as functions, priorities, etc... (a class), and the people weren't involved. Yet in the Constitution it says "We the People" as if the people had a say, no, only the rich diplomatic people. The Federalists thought that they were stupid and couldn't be trusted with such suffrage rights (voting), and with rights in general. Since the involvement of the other people was low and just a group was involved, it is a class based document. They say " we the people" as if they consulted every person, as if the persons said let's do it and so on and so forth. It is as if they are the people and no one else.