I'd understand if they wanted Kuyt but not Sculli.
He's average at best in my books.
Doesn't really matter. Every team needs to have cheap average players who can do the job of resting the superstars when the team plays the likes of Cesena and be enough to beat Cesena.
Inter's squad has too many quality high earners. 17 players earned 3m eur a year or more and only 5 players earned less than 2m eur. That's a receipt for a future disaster. Generally, 12-13 very good/great players are enough and everything more than that will create problems both in the locker room and the financial books.
Granted, Inter won the treble, but look at every other team who wins the CL and you will see that apart from the expensive stars, 40% of the squad is consisted of players like Zalayeta or Birindelli, who don't earn much, who don't posses individual quality but can come handy in the group.
Inter are probably trying to do that. Instead of Mancini or Quaresma who earn 3.5m or more, they'd rather have a Sculli on the bench who will be a 4th or 5th choice behind Milito, Eto'o, Pandev and maybe Obinna and who can play in midfield too.
If they bought Kuyt instead of Sculli they would have only created problems because he'd have taken the place of a superstar or be wasted on the bench while earning some 4m eur a year.