Despite these limitations, NASA still launches out of Cape Canaveral for two reasons.
1) It's close to the ocean. Along the coast, rockets can safely travel East over open water. Should there ever be an issue, operators can safely put it down in the Atlantic without putting the public in harm's way.
2) The closer you are to the equator, the faster our planet rotates. NASA takes advantage of this by launching rockets towards the East and letting our planet's natural rotation give the rocket an extra boost. Which, in turn, helps save fuel.