This means that each person "uploaded" 1GB of data and "downloaded" 3GB of data. In total, 16 GB of data was transferred. Doing this manually via USB drive is about an order of magnitude faster than over your average broadband Internet connection. It's not clear to me that Divvyshot has solved the problem here.
> I never ended up getting that group photo - even though low resolution copies of it tantalize me on Facebook.
I was surprised to realize several years ago that one of Facebook's greatest contributions to my life was that it completely solved the photo sharing problem and had done it so well that I didn't even notice. Now I get everyone's photos from every event, I get notified when they're uploaded, and it seems like everyone I know can use it without problems. Sure, I wish it supported higher resolutions, but the medium-res images are good enough for 95% of people. If they would just allow slightly higher resolutions, then it would be perfect for almost all of my needs.