There doesn't need to be any legal framework in place that doesn't already exist. Contracts can take care of that. Tokens are just a way to keep track of investments and simplify the process of collecting funds. Furthermore, it's impossible to regulate ICOs. You can only regulate the change from crypto into fiat, which most people won't ever care about.
I agree with you in that blockchain technology in itself is impossible to regulate as it was purposely designed to make any government regulation unenforceable. That's a good thing. However, legal entities can be regulated very easily. So as soon as you have some company regulated and registered in certain legal jurisdiction associated with particular blockchain technology, that blockchain technology can be also regulated. For example, government can brought legal action against that company and force it to change its technology to be more complied with government regulations. So yeah, anonymous ICOs would be impossible to regulate, however there doesn't seem to be a lot of those right now.
EDIT: Another important thing. Although blockchain assets are impossible to seize, control or regulate, this is not true for any other real worlds assets. OPs banana plantation can be shut down be government. Its property can be seized. So, when a blockchain asset is a representation of real world asset, it is susceptible to government regulation. In other words, making blockchain assets a representation of the property that exists outside of a blockchain itself voids the blockchain inherent resistance against regulatory interventions.