One of the ladies I work with sells fabric, both on eBay and Etsy. For her, Etsy is relatively new, within the last year or so; she's been on Ebay for quite a long time.
The vast majority of her sales come from eBay. She says anything from Etsy is just "an extra". Since she's already created all the advertising text for eBay, it's fairly easy to duplicate the listings in Etsy, since all the "thinking work" has already been done.
For what it's worth...