That does not identify you. That is for their use.
eBay does need your SSN in order to comply with the law regarding 1099-K reporting.
But that side, of course most of the information they request is for eBay and Adyen's use. It doesn't just identify you, it also qualifies you.
As someone who works in banking, you probably understand that banks don't just give loans to anyone who walks in off the street. They want to see a business plan, verify income, and see bank records that will give them some level confidence that the borrower is worth the risk. And they often want collateral, too.
eBay offers buyers a Money Back Guarantee. And just as a bank takes a risk when loaning money, eBay takes a risk when they agree to financially back any sale on eBay in the event that a seller fails to perform or suddenly closes his managed payments bank account to prevent withdrawals.
As someone who works in banking, you probably know that the level of information and collateral required of a borrower varies greatly depending on how much they want to borrow, who the borrower is, and what their finances are. I would assume the same is true with eBay - someone who is listing several $1,000+ items is probably going to be vetted more carefully than someone selling a handful of cell phone cases.
Now at the risk of going on too long ...
In your experience, how would a bank respond if the they asked for bank statements as part of a loan application, and those bank statements arrived "redacted" by the prospective borrower? Would that make the bank more comfortable taking that risk, or might it be a cause for concern?
