I made a copy of a campign without RSS, and the data usage went down to under a megabyte per hour. I agree, the support on the forum has been very good.
However i got conflicting information from live support, that made me search too far and wider than i had to. I understand that it is impossible to know every aspect of a product, but i am still not happy about the help i got from live support. When i had a data usage up to 6 Gigabyte per day, it did not help me when i was told "its normal, and just how it works." Another thing i was told, was that the campaigns where not cashed, that did not help at all. A little more information would helped me a lot. Instead i got misinformation.
I still have a lot of investigation left, because there was still a lot of data usage on test campaigns with only 2 jpg`s, but that could be other things like updates and such. I am relieved to know that it is possible to get data usage down again. I will update with results.