I would say because of the new exotic pet culture. Petshops are only there to make money, they can up thier prices insanely, because people will buy from them. My boyfriend works in a petstore, and as an example of what I am talking about, a betta home , just a small bowl with a nightlight attatched to the top is 49.99$Can, at Wal Mart, you find the EXACT same bowl for 14.99$Can.
As for thier livestock, you don't even want to know...a firebelly costs 35$Can, Oregon newts and paddletails cost around 40$Can, I could go on and on.
Usually the explanation as to why things are so expensive, is shipping costs. But, don't forget petstores are business, and work for the sole purpose of buying selling and making profit.
I a sure not all petstores are this way, but in my experience, a vast majority are.
Also, this particular type of frog may be more difficult to find, due to polluted habitat's, lack of habitat, global warming, etc.
