This is very typical of every state and is only of interest as a news story since it's California and Tesla, whose names typically attract a certain set of haters. However, as I have already stated, this is a very common practice for all US states and for all industries. States give sales tax credits for people installing manufacturing. It's a good investment since it produces more in future revenues, including income and sales taxes associated with the increased economic activity. It's particularly nice when you can support a growing industry rather than a dying one, and one that reduces our ecological impacts (does not eliminate, but improves- so we're always getting better, not wallowing in a pit of greasy dispare with the dying industries clinging to their politically stabilized markets and federal government destruction of competition).