1. Facebooks shared albums are limited to 50 users with a max of 200 pics. The average person at a gig takes 20+ pictures as an example. FB shared albums cannot cater for this.
Also with Facebooks shared albums its limited to your own friends, on Venteo its an open platform where people can collaborate in the same album because they are attending the same event.
2. Good point, when I tell people about this they always ask "really, how do I find it". FB have never really marketed it nor ever made significant improvements since day 1.
As a facebook "power user" I tend to make a private group and invite people to that group to upload pictures.
I've never seen the facebook shared album feature. It sounds pretty sucky to me!