Copy of the self-reliance plan. Make them fill it out and have a plan for becoming self-reliant on their own before you help them.

Talk to them openly about their choice to go to Disneyland while making the claim that they can't buy groceries.

Based on what you've written, I think your mindset is aligned with gospel principles.

Helping them maybe the right thing to do, but If you're not also helping them become self reliant, responsible adults you're enabling their behavior.