No, not really. I think most people here missed the point of the sign because it is not in context. It is just a photo of the sign and not viewed next to a grove.
People don't just steal "1" avocado. We're talking about truckloads. And I don't know when this law was put in place, but there was an avocado shortage a while back, they were worth their value in gold.
There's a small vineyard near where I live. I've seen people randomly go up and started picking the grapes with shopping bags. Eventually they put up a similar sign. However, I've also read a local article of some nice owner of a cherry grove. He put up sign and said it is ok for people to pick them and take them home to eat. Some neighbors were overjoyed and started picking them with shopping bags. But then 1 day, a group of Chinese guys showed up with a truck and picked it clean, then they took it to the local farmer's market and sold for profits. The owner had no legal rights b/c he put up the sign allowing people to pick the cherries. Needless to say he stopped after that.
Here, this will explain more:
https://www.nytimes.com/2004/01/26/us/someone-is-stealing-avocados-and-guac-cops-are-on-the-case.html
