Well, I discovered that I had different versions of hstore across several databases. Some were 1.1 and others were 1.3. On the 1.3 hstore versions, the \do *.|| produces a public hstore - hstore operator, while the 1.1 shows the same as public.hstore. Maybe I just wasn't casting this far enough. On both versions that operator shows as being in the public schema. My search path does include that.