Instead, they have mountains of fine print that with extraordinary care make sure the recipient has absolutely no property right in the business, no claim to any title, no voting rights, usually no rights to share in profits, etc.
If you wanted to liken them to something offline, they're structured more like making a donation and getting a limited edition t-shirt in return. Maybe with some vague suggestion, but no guarantee, that the t-shirt may entitle you to discounted services in the future should the business actually begin operations.
And this is before getting into the fact that a great many of them are essentially outright scams.
The fact that many people are thinking that ICOs are "just like buying an investment in a small business"-- is a great example of how the SEC is pretty much flat out failing at this part of their job.