The boxes are not the problem - they stay the same. The issue is with the envelopes. They fit up to 8 yards of fabric in them and you use to send them anywhere in the country for the same flat rate - NO LONGER. Now it's each package weighed and depending on where in the country or world you're sending them will be the cost.
This is a big deal when you're selling fabric to accurately quote people. I like to give fabric away as well, but this postage thing is a pain.