When you're scaling the slick cliffs beneath Angel Falls, you need something that can gouge into the hard rock. When you're robbing banks in D.C., you need something that can gouge into the helmets of cops.
The Ice Pick is a fairly powerful melee weapon, dealing high damage per hit and has a high knockdown value. It is blessed with a long reach and fast attack speed while also compact enough to retain a high Concealment rating to use in a Dodge build.
The only drawback to this weapon is its rather lengthy charge time.