I agree that it's not so useful for working with the table and queries. But,
setting the lookup properties makes that the default when a field is added
to a form. It is convenient to have a combo box generated automatically with
all the properties setup correctly. So I often do set the lookup properties,
just for that purpose. And it's convenient when looking at a table
datasheet, which is something only the developer should be doing, not users.
If you want to see the id value in a query, you can use TheID: id + 0 as a
column expression.