In my opinion, I would avoid creating extra DB collections unless they are absolutely necessary, i.e. you need to create records for something with very different characteristics.
In my opinion, data structure for food/drink/snack is pretty much the same: smth like Name, Article, Price, Ingredients, Picture(s), smth else. So why would one want separate collections for Pizzas and Burgers?
I would start with 2 initial collections: one for Menu Items, where all food/drinks will be stored, and another for Menu Categories for classification (a Menu Item can belong only to one Category).
With this it will be easy to organise lists on the screens with necessary filters, so that users can select what they want.
This could be extended with a subcategories (either separate collection or a “tree” with links in one collection), but IMHO for this industry it is not really needed: “flat” category list works pretty well up until 10-15 entries, which is pretty ok for a bar/pub/resto.
Please note, this is my personal opinion - there may be other ideas with different rationale.