Members already have semi unrestricted access to credit. Any member who currently sells on eBay works in credit through their access to listing fees and final value fees. I think that new members or non established selling members are restricted to the amount they can sell and thus the amount of credit they can access, so an internal credit check of sorts.
Obviously the amount of credit extended by the addition of the label service is similarly restricted to the amount of sales an account generates each month.
I would presume that eBay would not let unpaid monthly fees continue indefinitely, so there will be a point at which they will refuse access as would be both their ethical and financial responsibility.
In short, the established sellers have already earned their stripes and undergone their "credit checks" by keeping their accounts current until now, and the less established members are certainly restricted to the amount of debt which they can accrue.
How will eBay collect their bad debts? They will initially make up to three attempts to draw from the member's chosen method of automatic payment. After that, it will undoubtedly be referred to the debt collectors.
The scammers won't bother posting so they won't accrue any additional debts under this scheme (and if they do, I doubt they are high on their list of concerns), the recreational seller is unlikely to amass anything substantial in one month and those conducting ongoing business' are unlikely to reneg on their monthly payments, even if the system continued to allow them to operate as such.
I have never failed to pay my monthly eBay fees, what happens if you don't? I am sure I read somewhere about account restrictions etc, so to suggest that eBay are extending unsolicited and unrestricted credit is a bit of an exaggeration.
