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sure, why not?
Speaking of soft ice cream, I seem to notice that even the better quality ice creams seem to be getting softer.
Probably from more air being whipped into it.
I got a carton of Breyers Vanilla Bean and the ice cream did not touch the inside of the carton...like it shrank.
Still taste good though. Excellent with fresh diced mango topping.
I thought you would know to expect a little shrinkage with age!

Seriously, as a former ice cream plant employee, the volume decreases when the ice cream is getting old, or if it's not stored the whole time below freezing. Thawing for a short time and refreezing can cause the pulling away from the top and sides of the container, as well as frost crystals across the top of the product.
3 gallons of good quality ice cream weighs around 18 lbs. 3 gallons of sherbet -- 24 lbs (mostly water and sugar vs. cream). The density changes with ingredients, but it's all in that ballpark.
Do the math, and see if your brand is close to the per ounce weights I posted. If it's less, then it's possible they are doing something to increase volume, like injecting air somehow.
I've seen this in some brands, too, usually from WalMart. I bet they are letting it sit out and thaw too long at some point in the stocking process, or their freezers are being opened and closed so much, they can't keep up with the ambient temps.