I don’t think the assumption of equal transaction costs holds.
If I want to fill in some potholes on my street, I can go door to door and ask for donations—which costs me time but has minimal and well understood costs to the other contributors. If I have to add “explain this new thing” and “keep track of escrow funds” and “cycling back and telling everyone how the project funding is going, and making them re-decide if/how much to contribute” that is a whole bunch of extra costs.
Also, of the public good is not quantum (eg, I could fix anywhere from 1-10 of the potholes, amd do it well or slapdash) then the producer can make a decision about quality after seeing the final funding total, rather than having to specify everything in advance. For example, your website needs, say, 40 hours of work to be a minimally viable product, but could continue to benefit from work up to 400 hours. How many hours is the (suspiciously specific) $629 buying?
I don’t think the assumption of equal transaction costs holds. If I want to fill in some potholes on my street, I can go door to door and ask for donations—which costs me time but has minimal and well understood costs to the other contributors. If I have to add “explain this new thing” and “keep track of escrow funds” and “cycling back and telling everyone how the project funding is going, and making them re-decide if/how much to contribute” that is a whole bunch of extra costs.
Also, of the public good is not quantum (eg, I could fix anywhere from 1-10 of the potholes, amd do it well or slapdash) then the producer can make a decision about quality after seeing the final funding total, rather than having to specify everything in advance. For example, your website needs, say, 40 hours of work to be a minimally viable product, but could continue to benefit from work up to 400 hours. How many hours is the (suspiciously specific) $629 buying?