Sure takes me longer. I usually don't have to cut down boxes for domestic shipping. Pick the rightest-/closest-sized box, insert bike/frame, and Bob's yer uncle. Sometimes I'll shorten the end or lower the top if I need to, but it's usually not necessary.

Having to resize the box takes more time, and a 108" dim gives me less room for extra padding for bigger frames/bikes.

And FWIW, I didn't say anything about extra materials, just extra time/effort. Though I suppose you'd generally use more tape/staples having to resize the box, so, yeah, it does take extra materials. Quicker wear on your box cutter blades, too. Those blades add up over time...