On the eve of the $600 expiration, I think there are five key arguments for its continuation, based on available data.
1/n
(thread)

1. There was no evidence that it slowed the return to work.

Source:
https://tobin.yale.edu/sites/default/files/files/C-19%20Articles/CARES-UI_identification_vF(1).pdf
Data from:
@homebase_data

2. There was instead evidence that even with $600, the ratio of job applicants: job openings increased (they both went down, openings decreased more than applications)

Source:
https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3664265
Data from:
@Glassdoor

3. Workers who received the $600 spent more unemployed than they did employed. The boost to consumption is how an individual benefit becomes an economic benefit.

Source:
https://institute.jpmorganchase.com/institute/research/labor-markets/unemployment-insurance-covid19-pandemic
Data from:
@jpmorgan

4. That extra spending is important in propping up the economy right now; the BEA attributes the growth in income last quarter to unemployment benefits. They are about 12% of the size of all wage and salary income in the US.

Source:
https://www.bea.gov/news/2020/gross-domestic-product-2nd-quarter-2020-advance-estimate-and-annual-update

5. Anything more complicated that a flat add-on would take months to put into place, according to the National Association of State Workforce Agencies.

Source:
https://aboutblaw.com/Sdj 

Like I said before, the 160million+ workers in the US economy contain every edge case you can think of. There's definitely people out there who wont go back to work, shops that are staying closed so that their workers get money, and firms whose employees don't want to return.

But policy making needs to be informed by analysis, not anecdotes.

The $600 is getting money to workers in need; they spend it, which is good for the economy; and the effect on job search and re-employment is (so far) null. And the alternative, tailored benefit is not feasible.

I should add: the most important economic policy right now is containing the pandemic. We don’t have any evidence of whether the $600/week helps mitigate the spread. My intuition says yes, but I haven’t seen proof of that.