In answer to your questions. . .

In answer to Kathleen's comment about our homegrown corn:
Most of the time, our homegrown corn (in shucks) is near the mushrooms, off to the side of the produce department. It can be hard to see, tucked away behind a high display. That part of the produce department is one of my favorites, no trayed produce, lots of local stuff, and many ethnic choices. If you haven't visited it before, you're in for a treat.
In answer to the question about why we use styrofoam trays:
We have been desperately trying for over a year to get compostable trays.
It looks like we have finally found a supplier who has some that are sturdy enough for our use. Even though they are much more expensive than the styrofoam, we will be changing over to compostable trays as soon as we can get a shipment. Believe me, this has not been for lack of trying. Apparently, the technology is new enough that most companies have not been able to meet our needs.
The vast majority of our customers want their corn in trays. Otherwise, we would just pile up the fresh ears as they were in the picture you mentioned. Some folks want to see the corn they're buying. Like you, I prefer my ears packaged in shucks.
It is a high-priority goal of ours to have all biodegradable and compostable packaging. We never dreamed it would be so hard to find.