The first race ticket I bought, fairly early on in the game, turned out to be for Star Sprint. After finishing the race, it showed up as a completed quest in my log. Normally, finished quests disappear from the log after I've left the game and returned, but this one has stuck around for weeks now. I did not go into it as part of a quest, and have received no race quests from the magic rock (I assumed that since you could now buy tickets when you wanted that this was a change from beta, where you only got them as quests). So at worst, it's a bug that means I have not received quests that I should have, at best it's a small appearance bug that means it just won't go away. Still, something is awry.