There is only one Board Game Publisher that I know of in Los Angeles that hosts events where gamers and designers are both in board game heaven, and that is Breaking Games Studio. They host an incredible Open House about every month or so where designers can play-test their board games and players can give feedback.
For December, the play test event was at Geeky Teas in Burbank and there were 6 or 7 gaming tables for each 2 hour session, with multiple sessions throughout the day. Outside of the snacks and raffles, and access to some of the best designers in the area, anyone who attended was also given a free pass to Geeky Teas after the event was over (normally $5) to play as many games all night long. No big deal, just another perk on top of the already awesome day!
I highly recommend this Play Test event to anyone who is designing a board game, interested in designing a board game, or for those who love to play board games and are curious. The format is straight-forward. Play the game and provide feedback if you have any. Also, Breaking Games happens to be the publishing arm of AdMagic, and together they have published some serious powerhouse games including Cards Against Humanity and Exploding Kittens. And if the Designer Open House sounds like a lot, Breaking Games also runs more casual play test sessions at their studio in Burbank.