In a perfect world, you wouldn't need funding or UBI.

Why do you need to pay for food? Because that money goes to the vendor, the transportation, the manufacturer, and the producer, to transfer 'value' to them.

Consider the world as it may potentially be 250-300 years from now. Automation may have advanced to the point where farming is done in hydroponic facilities with no or minimal human presence. Same with mining, transportation, manufacturing, and so forth.

So who would you be paying when you pay for food? For the upkeep of the robots. Who don't buy things, who don't need medical, who won't have kids, who don't take time off, and so forth. And really, if you go farther, there's no reason maintenance on robots can't be done by other robots.