Not to worry - I’m just storing dry goods.
Is it because they are big that canning isn’t recommended?
>>>Is it because they are big that canning isn’t recommended?<<<
Yep... They determined that the temperature doesn’t get uniformly hot all the way through.
It is the same reason they give for not recommending canning thickened or pureed products. Like pumpkin puree - they now recommend that you can it as cubes so that the liquid will uniformly heat it up to the required 240º temperature.