In all seriousness, its poor list management for anything longer than a 4 year deal.Even then I wouldn't. Players are only a couple of bad injuries or a few bad concussions away from a severe dip in form or even retirement. 8 years is a whole career for some guys.
10 years for Buddy means his latter years are a crawl to the finish line, he's injury prone and slowing down on his output. Dusty could slow down in a year or two if he gets a bad injury.
Only thing I can think of is if you are very confident that a player has 8 years of footy life left, you could maybe save a million plus in having to negotiate his contract 2-3 more times throughout that 8 year period.