Birthday meal deal in WLA? Like Free cake, meal, drink...??
If you tell themas you make the reservation that it is for a birthday, they will "surprise" you with cake or a dessert in most places-from Benihana up. If it is your birthday, it's sort of better, appearance wise, to have someone make the reservation and set it up.
Very few places comp the meal. I do know that Musashi mini chain in the Valley will do a free dinner for one on their birthday, but the total party has to equal four. And the food ain't all that.
Ethnic places, such as Dim sum in SGV and Koreatown palces don't usually do it-it may not be tradtional in their culture and thus, it's just not thought of.
The best thing to do is to pick a place you or the birthday person likes for the food, and ask ahead of time when the reservation is made if there is a free birthday dessert/drink.
I think if you belong to the baskin robbin's club, you get a free kid's scoop (tiny). My dog gets a free cookie at three dog bakery on his birthday!