Hippies were a small minority in their time, not a majority like pop culture likes to depict.
And the older=more republican thing isn't really correct. It's more strongly associated with the party that was in power when you started voting and how good a job they were doing. If they were seen as good (Roosevelt, Truman, Eisenhower, Reagan, Bush), you'll likely keep voting for them. If they sucked (Carter, Nixon), you'll likely vote for the other party forever.