Since participants were given realtively minor one time payments, why would we expect their long term behavior to change? If one wanted to actually study the p

Since participants were given realtively minor one time payments, why would we expect their long term behavior to change? If one wanted to actually study the potential behavior impact of UBI, would it not have been better to study the potential impact of giving 500 or 1000 bucks a month for a year? I don't really think any rational actor would be expected to change their behavior if awarded a one time windfall of 2 weeks of wages.