"You've Earned a Reward"... No I haven't

Every time I log in, I get a couple pop ups in the top right corner of the client telling me I've earned a reward. Nothing new in loot (I'm up to 96 key fragments now), but I eventually tracked down the culprits: summoner icons. Cool. But I've got them now; I don't need to see a message telling me I earned a reward if there's nothing new.