One thing Jerry said that I actually found somewhat intelligent and has stuck in my brain is these draft visits also serve another unmentioned purpose and that is to make a great impression with the players. So that even if you don't draft them they may be free one day and it can't hurt to have already made a big impression on them.
I think that is true. Of course it's not the determining factor in free agent movement but it can be a factor in some instances. Show these players that Dallas is world class in comparison to the other stops they'll make around the league.