Packaging color is usually treated as taste. It is mostly arithmetic and physics, and on this particular pairing the two point in opposite directions.
Start with the price, because it is not what you expect
At the same 8 oz size and the same glossy finish, the glossy black to-go container comes in below the white equivalent. Not marginally.
Most shops assume the dark option is the premium one, because dark packaging reads as premium everywhere else. Here it is the cheaper line, which means the usual argument against going dark, that it costs more to look serious, does not apply.
What black hides and what it does not
Black hides handling. Fingerprints, smudges from a delivery bag, the general wear a container picks up between your counter and someone's table are all far less visible on a dark surface.
What it does not do is take a stamp or a handwritten label well. If your flavor labelling is a marker pen on the container, black is working against you and you will end up buying white labels to stick on it, which puts the cost back.
What white buys you
A blank surface. Glossy white takes a sticker cleanly, holds a stamp, and lets a printed sleeve or a hand-written flavor read at a glance.
For a shop that changes its look seasonally or brands by hand rather than by print run, that flexibility is worth the difference. For a shop with a settled identity that prints its own containers anyway, it is not, and the branding route with its lead times is set out in how custom printed cups work.
The counter has to agree with itself
This is where most shops go wrong. A black container is a decision about the whole counter, not about one item.
Black containers under white lids look like a stock error. Black containers with black lids, black spoons and a dark counter look deliberate, and the range supports that: glossy black lids exist at the matching sizes, and there are black dessert spoons and black flip top lids for drinks. If you are going dark, go dark across the visible items or do not bother.
White is more forgiving of a mixed shelf, which is a real advantage for a shop that has not settled its look yet and does not want every future decision constrained by one it made this month.
Deciding it
Ask whether you write on your containers. If you do, white, and the price difference is the cost of a system that already works. If you do not, black is cheaper, hides handling better, and photographs well against pale desserts.
Both finishes run across the takeaway sizes, and the lid that fits three of them at once is covered in one lid for 8, 12 and 16 oz containers. Everything sits together in the pints and to-go container range.