Well...once you have a Game Grid token in inventory, checking the game to see if there is a defective token could just as well be in breakfast, but I've been starting new BIG! ascensions and doing breakfast right away (why not, since I have MP to spare) and it takes a while before I'll have that token. From then on, I'd just as soon it were in breakfast, but having it as a Daily Deed makes it easy to check on the day when I actually get the token. I'd vote for breakfast AND a Daily Deed.
Now, regarding using a defective Game Grid token - I wasn't aware that it was a one per day item. I'm still trying to find one to load into my clan's Hot Dog stand.
But, looking at it, it clearly should not be in breakfast. You only get the granted effect for 5 turns and, as Fluxxdog says, you'll want to carefully time when you use it. That's a candidate for a daily deed.