They have not been discontinued. #IworkforWeber
Can you say anything about why they've become so difficult to find in store? Is this just on those places deciding to not stock them or something else?
I'm not aware of any changes in the distribution, but it can be pretty granular with different specific store locations. From my days in retail as a GM there was always differences in the A, B, C, etc. level store assortments, and the plan-o-grams were always changing. Could be that the stores you frequent in your area simply don't sell enough of them for the lighter cubes to keep their place on the shelf. I'm totally conjecturing. If there's still an empty place on the shelf for them to be stocked it's probably a matter of them waiting for stock to replenish from their distribution centers.