Some people are not going to extra lengths to get more money now. Those people might be happy with their current income, however low it is. These people will prefer to stop working.
You are also confusing money with wealth. Basic income may give people more of the first, but its inflationary nature does nothing for the second.
Sure, some people won't work. But most of those would be people who either would have a hard time finding work, or who have some specific other thing they'd rather be doing.