why would a seller not provide feedback? when it was all positive?

[harley_babes_hoard]

Feedback is voluntary they do not have to leave feedback. Some also have it on automatic, so when a buyer leaves positive feedback the system will leave it in return.
Feedback is not important for buyers really anyway.

[imastawka]

Your sellers only feedback was yours.  They have no other listings.

They probably haven't logged back in and most likely won't

leave feedback