This thread reminds me of what an SSPX priest told about the sin of gluttony. I asked him when was gluttony a mortal sin and he told me for it to be a mortal sin you had to eat so much that it made you sick.
See, that's interesting. We would assume that means that one ate so much they got sick immediately with nausea or vomiting and such. Yet so many millions are SICK today from the junk they are eating, it's just more of a slow death. It's not always immediate. In my mind, if a person knows better, and most have some level of consciousness that junk food is not good for them, then it MUST be sinful to some degree.
As far as the foods mentioned in the OP, I would counter that homemade versions of those foods can and do have nutritional benefits. Not enough for a family to live off them daily, but each has its benefits nonetheless.
Ice cream: Cream and eggs are a good source of animal fat, good for the brain. Add fruit, nuts or chocolate flavors and you get their benefits as well.
Cookies: These can be made of many nutrient dense foods such as oatmeal, dried fruit, nuts, butter/lard.
Soda: I would counter that with naturally flavored water kefir. Bubbly with any flavor you choose to give it.
Cakes: Flour, eggs, butter, milk -- all nutritious.
Chocolate: Dark chocolate is very high in Magnesium, the key mineral. Also antioxidants.
Chips: Potatoes are one of the highest potassium foods available. They are also a great source of the B vitamins.
It's really only today's mass-produced sugar & preservative-laden versions of these foods that are almost completely without merit (Soda being the only one I would consider completely
without merit). But we've taken substance out of our lives in every other way, of course we've done it to our food too.
In so far as people are becoming more and more aware of just how perverted these treats have become it does seem like they are opting for more wholesome counterparts whenever they can. But it does take more work to make them at home as opposed to stopping by the corner store, so they get put in their place as true treats to celebrate special occasions. You can't be making this stuff everyday, other than the kefir.