I know I have like a bajillion QuackerJack headcanons/ideas/whatevers already, but hear me out for this one that combines a few of the classic earlier ones I did:
The day QuackerJack snapped was just like any other day, or at least when it started. After spending weeks as a shut in at his own house (he was getting tired of all the news coverage of his latest blunder with his products that he insists is a misunderstanding), he decided it was time to go on a grocery run, since his pantry was getting thin on selection, and he wasn't going to resort to using ketchup in place of spaghetti sauce.
He goes to the store, in basic civilian attire to not draw attention, opting to walk (despite it being a poor choice to carry a lot, but he just wanted to take advantage of the sunny day and good air), taking note of the various advertisements along the way for this new fad that the kids are all going nuts over: Whiffle Boy.
Advertising such as posters plastered in the store windows, a billboard or two mentioning the bundle deal with the appropriate console to go with it, and tie-in meal deals at the local Hamburger Hippo burger joint. Ooh boy, it's just about everywhere, so he keeps his head tilted down to avoid looking at the smug face of that ridiculous guy. He's going to the store to buy a few things, and he doesn't need to make a scene about it...
He gets to the store and grabs a handbasket, intending on getting the basic essentials: Milk, bread, eggs, maybe some sandwich supplies (particularly peanut butter and jelly), probably a box of cereal, and his heart is set on getting a package of bacon at least.
There's just a bit of a problem. The bacon package has that godforsaken Whiffle Boy printed on it, advertising some sort of sweepstakes. All of the bacon in the fridge case has it on them.
Trying hard not to lose his cool, QuackerJack slaps the package back on the shelf with more umph than he intended, which unfortunately triggers a loose fastener on the shelf to collapse, creating a chain reaction of the rest of the fridge case to follow suit.
20 mins later, after insisting that he'll pay for the damages when he can, he finds himself at Hamburger Hippo, hoping to at least be able to grab something to eat for the night and try his grocery trip tomorrow. Whiffle Boy promotional material is all over the establishment, even the hippo shaped building has been fitted with decals to mark the tie-in. The wrappers, the bags, the boxes, the cups, even the straws and napkins, much to his astonishment and annoyance.
It's only temporary, he assures himself under his breath. It's just a fad and like all fads, they go away with the next big thing, and he'll be sure that next big thing is one of his products...
Aside from the slight oversalting of his fries, the food itself wasn't much to complain about. Oddly enough, the soda fountain was out of order due to the constant sales of the promotional meal deals, so he was offered an upgrade to a milkshake of equal size for the price of a soda. Ah, at least one thing seemed to be going right for once today...
Walking back home now, carrying his sack of fast food, he passes by a brick-and-mortar game store, which he averts his eyes to as he take a sip of the milkshake. He realizes all too late that the door has swung open in his way and smacks into his face. A duck in a green sweater vest steps out, holding a fair sized box adorned with Whiffle Boy logos, graphics and decor. It's a gaming bundle box!
Blinking slightly in pain from the door bending his beak back a bit, QuackerJack hears the duck thank the store clerk, commenting on how his kid was going to love the console, and couldn't wait to set it up for a round or two with her once she got home from school.
QuackerJack couldn't help but notice that the duck didn't even realize or acknowledge that he'd slammed the door in his face. He took a second to check on the bag of food in his hand, which was amazingly unscathed. The milkshake, however, had been launched into the road. Where the duck unknowingly ran over its remains while leaving the parking lot.
Trying his hardest to keep his cool, QuackerJack continues home, sits down with the food bag, and realizes that they forgot the cheese on his burger. And there was a complimentary Whiffle Boy action figure tucked into the bottom of the bag.
This was his origin story.
