I have a Kobo (Canadian) and archive most of my books into my account online once they've been read. I love reading on my e-reader but keep a physical book also on the go as well. The Kobo is for bedtime reading since it's so easy to hold and the lit page doesn't tire my eyes. I should look into loaning books! So often I've read a book and thought "so-and-so would really enjoy this book" but I can't exactly just give them my device. Like Onebyone I have a Bookbub account but it's led to me owning too many mediocre books. I count them as fair exchange for the gems I do get.
This is an interesting topic, having never thought about an e-reader as passing along a library.