Technically yes, but you will do it at your own peril since Steam MIGHT not like it.For youtube I only have to change my IP and I`m able to watch videos which aren`t available in germany.
Does this also work for Steam because it reduces my traffic only slightly. What is when steam looks which data is behind my IP-adress, and there isn`t data like country, city...
behind my IP?
They very, very likely will never do anything about it, but they theoretically could.