Where any UBI funds would have to come from - from individuals with high incomes. But instead of enforcing it through law, supporters of UBI (many of who on HN certainly would fall into the high-income category) start voluntarily supporting individuals that they think would benefit from BI most. The benefits are:

1. This starts creating positive effects of BI right away, just not for all.

2. It gives a practical example of the beneficial effects BI might have.