They don't expect you to kill 6 more deer. Hunter success rates may only be 1 deer per 4 tags , or 2 deer per 5 tags, etc. They may issue 200,000 more tags and see a 30% harvest rate.
And you sure don't have to kill 6 if you don't want to. I carry 4 tags (3 doe/1buck)here in PA. between DMAP tagsand regular buck and doe and only take 2.