You have to understand that the welfare fraud which is present now is probably a lot more prevalent then it could be if UBI is present. Because with the current welfare system, if you fake your income levels (or something along these lines) you're going to be allowed to get welfare.
UBI is a system which gives to all (maybe capped out a certain point, but still) and avoids the tediousness of having to screen mass amounts of people.
I can agree that there will probably be less fraud. It's a bit simpler to fake income than to create a completely new identity.
I was just reading about a pilot program that's happening right now in Ontario, Canada, if I understand correctly:
https://www.ontario.ca/page/ontario-basic-income-pilot. The numbers there are quite similar to what we've been talking about here. It's intended to be an "income that will meet household costs and average health-related spending." This is how much there's giving:
Following a tax credit model, the Ontario Basic Income Pilot will ensure that participants receive up to:
$16,989 per year for a single person, less 50% of any earned income
$24,027 per year for a couple, less 50% of any earned income
People with a disability will also receive up to $500 per month on top.
It's only for people that are earning less than $30,000 or $48,000 as a couple. It seems a little weird to me. It you make $20,000, they'll only give you about $7000. They you'll have $27,000. If you don't work at all, you'll have $17,000. It seems like there could still be a tendency to work less. There would definitely be a huge desire to falsify income info, when every dollar means you lose 50 cents of what the government would give you. It looks like the first pilot program may actually be complete, but I can find the details yet.