Not weird at all. I've used dates in cyser, as per Ken Schramm's Fall's Bounty Cyser recipe, though I didn't really notice anything in the way of date or even date-like flavour from them. People have been making date wine for at least a thousand years, probably a lot longer. Jack keller has a couple of date wine recipes: http://winemaking.jackkeller.net/reques64.asp
Hope you find this info useful. Regards, GF.
EDIT: You should check the pkg to see if those chopped dates have been rolled in oat flour. Oftentimes they are, to keep them from sticking together too much. I'm not sure if oat flour would be a big problem or not as I've only used whole, pitted dates without oat flour & chopped them myself. Regards, GF.