Why didn't Splinter use his psychic abilities to win the lottery?
 

The Central Intelligence Agency used remote viewers - psychic spies who could send telepathic messages back through time to themselves. So why didn't Splinter use his psychic abilities to send a telepathic message back through time to tell himself lottery numbers? Then April could have bought a lottery ticket and she, he, and the turtles could have been rich and they could have helped the poor and like build orphanages.

And what makes you think he didn't already...

... well, someone has to pay for all these hot pizzas somehow, right?

I can't imagine that that would sit very well on Splinter's ethics. I mean, if he could do that, there's literally nothing outside his range of influence, and he'd probably use the power to defeat Shredder or something. There're also a few time paradoxes that would conflict with that.