I often tout the benefits of selling my books at all online retailers (termed "going wide" by some). I sell books directly through Google and a few through Kobo or BN. But for the most parts, I sell non-Amazon books through Smashwords, an aggregator who puts my books on many sites. For this, they take a small percentage of a sale.
Smashwords also sells books directly through its own store. This gives me great joy. Every week when I look at books sold directly by them, I see the buyers' countries. Look at today, for example.