I also contacted Etsy.com, here's their email response:
Thank you for writing, as well as for your idea for improving Etsy!
We do realize that many of our members would prefer to submit electronic payments on Etsy without the use of a third party processing service, such as PayPal, and we are currently taking that into consideration. While I can't really tell you when or if such a feature would be put into effect, I can assure you that it's not something we've forgotten. I will definitely pass along your link to our engineers!
Thank you so much again for your suggestion! We really do take member feedback into account when making changes to the site, so it's always nice when someone writes in with ideas. 
Let me know if you have any further questions or concerns, and have a nice day!