Do you still need created_by and updated_by attributes with dedicated auditing?

For as long as I have been writing database-backed websites, I have included created_by, created_at, updated_by, and updated_at in every single table. As you can guess, whenever a record gets created or updated the appropriate fields are set. Currently I'm working on an auditing module for my website so that every insert/update gets added to an Audit table along with the field values from the record being changed. Habit has me still adding those create/update columns to each record but I'm wondering if they are even needed anymore.

Are created_by/created_at/updated_by/updated_at fields still necessary or helpful if those same actions are being tracked in a dedicated table?