I built an internal dashboard once that displayed thumbnails of building plans. Actually no, I built the dashboard, then the new guy added the thumbnails, but anyway. We didn't actually have a thumbnail generator because the sprint for that was skipped. Most of our users had only a couple of projects so even if each image was several mbs large, it wasn't that huge of an issue for them. The internal dashboard though, loaded a thousand projects per page.

I chewed through 7Gb of data in about 30 minutes while working tethered to my phone.