Dragon Scale shouldn't exist

I've gotten a 7 day pokestop streak many times in the past few months and as of now I have three dragon scales. It's only use is to evolve Seadra into Kingdra. While there is another evolution item, King's Rock, that's used to evolve pokemon into "king" themed pokemon. I just think it's annoying getting these when I'd rather get something like a Sinnoh Stone. I do realize dragon scales are in the main line games, but I think it makes more sense to have it be King's Rock. Had to vent sorry.