Meh. Wonka products aren't anything special. you'll find them in Aisle 5 of most supermarkets (cue those who have a different aisle number).
Who cares if Dreamworld has more of the product. Theres no exclusivity with the product. it isn't licensed by or from WB, and nobody can blame MW for not having it - if i want to buy candy at a theme park, i don't want to buy something that will be overpriced (because a bottle of coke costs $5) that i can get elsewhere.
When I worked at Wonderland, I would regularly visit the retail plaza after my shift. When I bought confectionery, it wasn't a regular off the shelf item - it was the giant lollipops and twisters - this sort of thing:
give me something unique, and i'm more likely to buy it. for all I care they can get rid of all the wonka products entirely.