The etymology and typology of "trash bean"

Kindly contributed by C, here's a sign from the toilets of a restaurant in Jaén:

Don't though any papers into the water close. Use the trash bean.
There is too much material here to deal with in one post, but we can report that modern forensic linguistics, combined with a couple of glasses of wine, have led to the discovery that "trash bean" is the work of a team from the University of Jaén consisting of a semanticist and a phoneticist who have been moonlighting happily but not always completely successfully as tourist copywriters. The base conditions and sequence of events were as follows:
  1. Dr Semanticist is a rough and ready field lexicographer who has acquired some notion of English semantics but continues to struggle with phonetics.
  2. Dr Phoneticist on the other hand is a somewhat unworldly type who is pretty comfortable with English phonetics but not semantics.
  3. Dr Semanticist, who knows what a bin is but can't pronounce it, is dictating to Dr Phoneticist. At the moment of truth he performs the characteristic Spanish [ɪ] → [i] transformation.
  4. Dr Phoneticist transcribes the semanticist's pronunciation correctly in accordance with one of the options available in English.
I think what they have come up with is a translingual malapropism, commonly known as an Irish bull because of Irishmen's supposed propensity for this type of error due to their unfamiliarity with the English language. But is it really a mistake? Certainly an Indonesian company called Oliqus appears to have commenced the industrial production of trash beans, which, while they superficially resemble Western trash bins, may for all I know have bean-type pod functionality. More research is required.