His actions made perfect sense from his utilitarian Effective Altruist worldview. He was stealing from rich people, and giving the money to what he saw as "worthy causes."

He was pretty open even before the collapse about how he decided to get as rich as possible, as fast as possible, at all costs, as long as (in his own moral calculus) the net benefits were positive.

EAs are arguably a 'cult' obsessed with AI risk, which they mostly believe will end the world in the next few years. So to them, that pretty much justifies anything that could help mitigate that risk. He would see it as immoral not to become a criminal in order to fund AI risk research.

Personally, I think these AI risk concerns are legitimate, but I don't agree with these methods.