As Love4Mom commented, feedback received as a buyer doesn't mean a lot but there's another very important reason why sellers wait for buyers to leave feedback and why even after the sellers receive feedback, they may wait a few days to leave feedback for their buyers and possibly not leave feedback at all.
As much as ebay wants buyers to leave "honest" feedback and assures buyers that their feedback and DSR ratings are anonymous, there are tools sellers can use to determine whether those buyers have dinged a seller's stars while leaving what appears to be "glowing" feedback.
And in order for sellers' reports to be updated, it can take from 24 to 72 hours after feedback has been received by the seller. So before a sellers leaves feedback, they want to verify that the buyer didn't ding their DSRs.
(Several years ago, I sold something to a buyer who was also a seller. She kept bugging me to leave feedback for her, telling me she'd left "5 stars across the board" and to do the same for her "since she gave me such a smooth transaction."
Well, 48 hours after her feedback was left for me, I ran my reports and saw her "5 stars across the board" were actually 2 stars in every category.
I wasn't allowed to tell her that I knew what she'd done since it's supposed to be "anonymous" but I added her to my BBL and also never left feedback for her.)