The difference between saving free work and acquiring a paid Item.
Your Library is a durable record
Library contains work you saved, added, or purchased. A free acquisition can unlock supported playback, reading, or downloads; a paid acquisition is added only after verified payment.
Remove and re-add
Removing an Item hides it from your active Library view. Re-adding it should restore the existing relationship instead of creating duplicate purchase or entitlement history.
Store visibility is separate
A creator or administrator can remove an Item from public sale while preserving buyer history. Access still depends on the Item, your current entitlement, and any refund, reversal, dispute, or legal restriction.