Oh. I hadn't heard of it because it's not quite accurate. These two article more accurately reflect my experience.
http://www.dailynews.com/news/ci_19927318?source=rss
http://www.mercurynews.com/breaking-news/ci_19937126
The quote, "We don't ticket anybody for throwing a ball on the beach, as long as they're doing it responsibly," sounds exactly right. According to those articles, the lifeguards will move you only if the crowd warrants it, and you'll get ticketed only if you don't move. The beaches here are very wide, so realistically you'll just get moved inland a little bit. No big deal.
There's always someone playing catch on the beach (whether a ball or a frisbee). I've done it myself. I've never heard of anyone ever getting a ticket. I also dig holes with my children every time we go to the beach, and I see other holes all the time. I've never heard of anyone getting a ticket for digging a hole.
The lifeguards drive Ford pickup trucks. Last year a lifeguard drove over a sunbather. I don't know if he got a ticket or not.