You are wrong, that is not true at all. We confiscate the items, sometimes deny entry, and sometimes ban future entry. It happens all the time with pharmaceuticals, produce, and any number of other goods that are legal elsewhere but not here. Spending tax money to imprison people for years over minor cultural differences and misunderstandings is absolutely brain dead policy.
There are already 5 cases like this because this is a super common mistake and T+C recently implemented a change in their policy for handling it.