Because he asked for a "High End" jack. Much of Fenders hardware (the stuff used in the "Squire", "Standard", and "American Standard" lines is not "high end. Fender's good stuff is used in their Custom Shop pieces and in the American Deluxe pieces.
It's just easier to get quality stuff from Carvin as they use the same grade in all their pieces. That's all.
That said, really any jack will do if you're using it for club dates. If you're doing digital recording, the higher end stuff makes less noise, and depending on the quality of your cables, produces a truer representation.