In this episode, apparently every Motel 6 in America is holding a beekeepers convention. Motel 6 in the 1980s was a notoriously no-frills hotel chain that went so far as to not even include a TV in their rooms unless you paid extra for it, and like actual roadside motels, did not hold conventions of any kind at them. Furthermore, even if they did, it is extremely unlikely that every location in any hotel chain would be holding the exact same convention at the same time.
If Alf is driving on the freeway towards Oxnard (likely US 101, or "the 101"), he would not pass a Motel 6 so closely he would see it nor would bees from the beekeepers convention be able to invade the car.