Yes, holes exist and are a useful formalism. But you are wrong, holes very much behave like other elementary particles (pseudo-particles), and you get to call t

Yes, holes exist and are a useful formalism. But you are wrong, holes very much behave like other elementary particles (pseudo-particles), and you get to call these things particles, exactly because they behave like excitations of a field. If you insist, sure, you can make up an infon and call it a particle. However, it would not behave like anything a physicist would call a particle, nor would it use any of the mathematical tools that were developed to deal with particles, nor it would provide any useful intuition or insight, nor would it provide any pedagogical value. And at that point why bother calling it a particle if it does not behave like one.