SimpleForm unnecessary access the database for associations

[jacob-carlborg]

I've noticed that simple_form eagerly fetches records for an association. Example:

<%= f.association :foo, as: :autocomplete_collection, url: foo_path  %>

That's completely unncessary since the collection is never used for the :autocomplete_collection type. The whole point I'm using this type is because the data in that table is very large. Is there a way we can add an empty collection option, collection: [], somewhere?