I could be mistaken but it looks like the $5,000 is from the CA Computer Crimes statute. For larceny (theft of personal property) in CA the bar is even lower: $950.
I was charged with theft under 5 when I was 14 after stealing two candy bars and a drink from Walmart. Same charge as I would of had if I stole a 70" flatscreen TV, or a top of the line computer.
It basically comes down to if you steal more than $5000 you might go to a very bad place and if it's less, you only go to a slightly less bad place. The line has to be drawn somewhere, and no prison is a particularly good place so it really hardly matters.