Lookups in tables are just a way to avoid having to make the necessary and properly related tables. They also support the ability for users to muck about in the tables directly, which is another thing that is generally considered to be bad practice. While you might have combos on a form, they're not used in place of table lookup fields. They're used in conjunction with properly designed db schema and that means having the right tables with the right fields for the job.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.