Makes no sense
When the birds attack the town, a bunch of people are huddling safe in the diner. Then, for no reason, they go running outside, putting themselves in harm's way. Why?
shareWell, first it is a small group of men -- led by hero Mitch Brenner and the sheriff -- who run over to the gas station to help the attendant fallen by a bird. So...they're covered.
I think the others flat out panic after the explosion hits. They have two choices: huddle in the diner or RUN FOR THEIR LIVES (to their cars and escape maybe.) They choose RUN FOR THEIR LIVES until they realize the birds are so plentiful that they have no choice other than to run back into the diner(plus some STAYED in the diner to begin with.)
Critics -- then and now -- seem more upset that teacher Annie Hayworth and protagonist Melanie Daniels instruct the school kids to leave the safety of the schoolhouse to run to town, but "on instinct," Annie and Melanie probably figure "these kids should go home or into the safety of town, not remain as sitting ducks in this building."
All this panicked running around got The Birds some bad reviews at the time and some laughs now, I guess.
Back up one movie to the more scary and logical " Psycho." Unwitting victims are simply pounced upon by a knife wielding psycho killer, the victims have no time to think about escape and then no place to escape TO. Its a real "sudden death" movie. The Birds allowed for more "running around" and hence drew some doubters.
Its not fatal to the movie, though. Just weakens it.