This is a 2 birds and 1 stone scenario. Keep in mind good/great GMs are students of players. How often do you hear a GM/Coach say "we were high on him coming into the draft"?
GMs and Coaches study as many players as they can, regardless of need, before the draft. Many they will keep up with throughout their career. It serves many purposes. While they may not be able to be in a position to draft the kid, they may be in a position to acquire him via trade or FA down the road. They don't want to have an unknown quantity or point of reference in their analysis of a player at the moment he becomes available. If Hickey didn't follow Moreno coming into the draft, he would not know if certain qualities he has now could be seen back then. Furthermore, he wouldn't know if some habits were acquired after being drafted or existed before.
You can't know everything about a player, but the more you know about his history and current skill set can help you make a better judgement. Also, if a unique player comes into the league GMs watch his development. They look for techniques that helped him succeed and/or fail. When they see a similar player coming into the draft in the future, they have a better understanding of what is needed to help him succeed on their team. How many people here understand that being able to develop Russell Wilson probably has a lot of teachings from Drew Brees' career in it?
Do you think every good GM in the league hasn't watched Cam Newton and RG III's development?
You may not draft a kid, but he may be able to teach you a lot for the future.
The second stone is using the veil of a major name player's Pro Day to inspect lesser known players also their. Maybe Mike Evans is a target, maybe some OLineman, as well. Either way, it shouldn't surprise anyone that Hickey and Staff are out there doing their job.
It does make me wonder why Hickey hasn't sniffed on Blount yet. I mean, he does have first hand knowledge of the kid. Maybe he's an "after the draft" possibility. Because I think we all agree that Moreno is more like Miller. We still need someone to replace the role of DT.