I agree things were easier when they delivered it in bags though.
Is this some sort of deranged lobbying scheme?
I don't think so. This is largely dependant on each grocery delivery service, but of you look at it the worst cases are actually just continuing business as usual,which is hardly a regression. In the meantime, some services managed to completely eliminate the use of plastic bags.
As an example, for the past year or so I had a groceries delivery service use their old plastic bags, but they also implemented a charge-back service where they pay you back when/if you return them in the following delivery. This is clearly an improvement. In the meantime I had competing supermarket chains completely switch away from single-use bags to alternatives such as reusable plastic crates and even reusable cardboard crates. Behemoths such as Amazon Fresh completely switched to a mix of paper bags, for example.
Bonus: the KLT system easily offers enough assistance to automated/mechanized handling that the box delivery task doesn't require humans.
Could probably easily have a portal crane style 4-wheel robot to drive the new box from the van to your door, drop it, and bring back an empty box you put out for it.
Well, something about curbs, but the stair dolly (big wheel made of 3 smaller wheels) style drive can probably cope with most.
Originally the KLT boxes were made to elide re-packing and manual box handling in the many-small-supplier-companies car industry of Germany. They differ from the more widely seen euro boxes by having molded features to allow a robot gripper to "plug" into any of the 6 sides of the cuboid and get a solid grasp of the box suitable for (re-)stacking them as long as their nominal load rating is adhered to. Also at least one, if space a short and a long side though, have a slot to hold a DIN A-series piece of (tick/heavy) paper describing the box contents, such that the box won't be contaminated with sticky tape residue.
When they're eventually broken from old age or abuse, they can be recycled cleanly because they are normed to be a pretty specific plastic and to (for interchange at least) be one of that colors (grey and a dark blue).
I have seen a local service, picnic, using a small urban-only electric truck (if not even a tricycle) who's back is just a 120 cm (plus tolerances plus door thing) wide shelf to be used with 40x60 cm euro boxes. If they were KLTs you could just put the box as-is in your pantry instead of doing the "dump onto kitchen table" tactic, I guess.