over 2 years ago - Roxx - Direct link

The official stance on this is that VPNs are not allowed due to both Valve and Amazon ToS.

The reference can be found in section 5.2 of Amazon ToS: https://www.amazon.com/help/ags/terms

Even if you are not using the VPN to get around Geographic Restrictions specifically, our legal team has informed me they are still not allowed to be used, so I must advise not to use them as your account may be banned.