I can borrow as much as I can read from the library, but I can't keep the books I haven't read at home while I am not a member. The books never really belong to me, just as the HP ink never really belong to users (until they are printed onto paper, at which point they become a constituent part of a "page" which _is_ owned by the user).
I think the cognitive dissonance arises because this "borrowing" model is being applied to a _consumable product_, which is not common.