The laws generally say it is illegal to "knowingly" sell to a prohibited person, but if the state can't prove you "knowingly" sold to a criminal, you have no way of proving you didn't know.
You're statement is very confusing. If the state can't prove you "knowingly" sold to a criminal, what need is there to prove you didn't know the buyer was a criminal?
Even if the sale is legal, if things go badly wrong, "they" will find some way to get the seller.
"get to the seller"
Why? Are you saying the state is corrupt?
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