The larger dewars are tall cylinders to conserve floor space, the lower volume ones get to be shorter and fatter.
If the Dewar shapes where the same and the sized changed certainly but in practice I found that LN2 is lost faster in a commercial tall 180L then a
shorter fat storage 25L. In a good brand new 1L vessel the loss is almost unnoticeable.
I calculated it out back when I ordered the stuff and it worked out to an average of .3 of the total volume of a large dewar per day going off as gas.
The bigger dewars also have a lot of plumbing which dips into the LN2 and possibly greater vacuum loss as the tanks are bumped around and shipped.