With no reason to save I could do whatever I wanted. Walk all the way to Everest, swim the Atlantic, tell my boss to fuck off. As for wealth, I'd spend decades hacking into bank accounts, because why not? What are they going to do send me to prison?
If we could all be immortal it would kinda suck to be wealthy. No one would need your wealth, and if you they did you'd spend all your time trying to protect.