[disgruntledphd2]

Hmmm, that's really weird. It's probably an edge case that would be complicated to change in that case (never underestimate the power of inertia, especially in ML systems).

[joshspankit]

I feel like it might be almost trivially solved with a “buyer only needs one [for X months/years?]” property on the items.

It would likely have to be added by a human, but still: there are a relatively small number of items that people only need one of.