This 'bulking up with air' is most evident if you go to the yogurt or cream cheese section and look for the Yoplait Whips or Philadelphia Whipped containers. It's the same product, just as a foam, and seems to be marketed as a healthier alternative where users choose a satisfactory portion by volume, not by calories or weight.
And while I think the whipped foods are stupid, I don't think that packaged food sellers are necessarily scumbags. They're merely people responding to incentives, just like everyone else. The food market has razor-thin margins and consumers are ill-informed. Neither consumers (who are hard to inform) nor regulators (who are captive to the multinational conglomerates) have been able to push back more strongly than the profit incentive, so the so dark patterns like those you describe are inevitable.
Plenty of dieters do this themselves with protein fluff/"ice cream" (protein shakes with ice and xanthum gum). Overweight people almost by definition eat by volume not by calories (ie they eat more than their body needs for caloric maintenance).
It's not entirely true that regulators haven't plushed back: in the USA, there's a minimum amount of cream required before the vendor can call the product "ice cream".
The products in that category that have been puffed up with air (and don't meet this minimum) get sold as "dairy desserts".
(I don't work on the food industry, so I won't be shocked if I got details wrong.)
Which is exactly why McDonalds menus list "cones" and "sundaes". Not "ice cream cones". It's a frozen dairy dessert that is not legally ice cream. To be fair, McDonald's version is superior to any other fast food frozen dairy desserts that I've had.
The bulking aspect doesn't bother me so much, what does bother me is that it's not as good and the only major ice cream brands left that aren't like this are Haagen-Dazs and Talenti.
And while I think the whipped foods are stupid, I don't think that packaged food sellers are necessarily scumbags. They're merely people responding to incentives, just like everyone else. The food market has razor-thin margins and consumers are ill-informed. Neither consumers (who are hard to inform) nor regulators (who are captive to the multinational conglomerates) have been able to push back more strongly than the profit incentive, so the so dark patterns like those you describe are inevitable.