If you mean you wanted to commit to the Buy It Now price but pay later, that is still available on some listings, but for most either the seller or eBay chose to make Immediate Payment Required according to their own judgment because there are too many non-payers out there (including scammers). If you click on the BIN button and are taken to a payment screen (if you mean something else by "BLIND CHECKOUT" posting screenshots would help us diagnose what you are running into; also if you are seeing a listing with an Add to Cart button but no Buy It Now button which is something I've never seen) it means either the seller or eBay chose IPR, the difference being if eBay requires it but not the seller you can "Request a total" for multiple items from that seller (assuming none of the other items are IPR by the seller) which commits you to pay and removes the item from inventory (ending the listing if it is just that single-item).
