Money exchange rates in Austria (Vienna)

I was in a visit to Vienna the last week, I wasn't aware of the euro exchange rate so I exchanged about Protected content Riyals to euros, the guy gave me Protected content
that means the exchange rate is 7.33

when I'm back to home I checked the exchange rate and I surprised when I found it 5.6

with a simple calculation it means that I lost Protected content

I called the place where I exchanged my money it is called "the change group" and explained what happened.

the guy replied me: it is a free market and the rate here is 6.55 and there are additional 10% service charge ......

and changing money from airport costing more than changing it from any other place

honestly it doesn't make sense for me.

does anybody have experience in money exchange in Vienna? !!!