Using a VPN is not illegal. Users have the opportunity to participate in ICO. The developers formally take responsibility for the fact that accept Americans. All conveniently. I think this proves the absurdity of the ban. The government do not know how to use inventions for the benefit. They used to only act prohibitions. So people are forced to go to the deception.
What about the legalize and TOS outline in the whitepaper? Wouldn't you be in violation of circumventing those restrictions? There are various whitepapers that have different clauses, but one that caught my eye was EOS. Basically, if you use a VPN to participate, you will then be liable for paying for the legal costs of EOS if they are taken to court for soliciting unregistered securities to Americans.
Here is a direct quote from their EOS distribution paper:
"U.S. persons and Chinese persons are strictly prohibited and restricted from . . . purchasing EOS Tokens and Company is not soliciting purchases by U.S. persons or Chinese persons in any way. . . Company is not bound by this Agreement if this Agreement has been entered into by a U.S. person. . . and Company may take all necessary and appropriate actions, in its sole discretion, to invalidate this Agreement, including referral of information to the appropriate authorities. Any U.S. person or Chinese person who uses the EOS Token Contract and/or purchases EOS Tokens or enters this Agreement on an unlawful, unauthorized or fraudulent basis shall be solely liable for, and shall indemnify, defend, and hold harmless block.one . . . from any damages, losses, liabilities, costs or expenses of any kind whether direct or indirect, consequential, compensatory, incidental, actual, exemplary, punitive or special . . ."
Here is an article explaining it better:
https://cryptoattorneyblog.com/news/2018/1/10/eos-a-tale-of-crypto-insanity