Hi I just bought a game for $4.95 and saw the only option was paypal. That's great for taking and and all international transactions... But since I'm in the USA I was able to pay via Dwolla which has 0 transaction fees on payments under $10, and only 25cents above.
I run a small business so I'm sensitive to paypal/credit card fees and don't particularly like knowing they are getting a slice when I'm paying for something, when cheaper alternatives exist. In this case, Paypal probably took ~2.9% + 30cents of 4.95 = 44cents with is nearly 9% of the entire payment. Ouch!
-Avi Disclaimer: I do NOT work for dwolla, I'm just a huge fan of lower/no fees.
I doubt if this is likely to happen anytime soon... According to Wikipedia, Dwolla has only 20,000 accounts, while Paypal has 100,000,000+ accounts. So, the game developers are naturally going to go with the obviously more popular method rather then try and appeal to a market of only 20,000.
Even if used as a second option to Paypal, it probably wouldn't generate enough money to even be worth it to the developer to include it.
