But do you think, in general, if someone is being extorted by an individual, that the person 'structuring' should receive a higher penalty than the blackmailer who is demanding payment?
The blackmail could be the result of the blackmailed person committing a crime.
Sure - and that's the obvious exception. But in the sole context of a structuring case, I think too many innocent people get snared.
One is more likely to expose a blackmailer than commit the crime of lying to the Feds unless one is guilty of some crime. If one is blackmailed for something that could simply be embarrassing, then it is the blackmail that is the crime. The recipient of income from blackmail might then be subjected to some other crime -- let us say money laundering or tax evasion.
So let us suppose that some conservative politician has a black great-grandmother that he wants to keep hidden because his campaign is based on barely-concealed themes of racial animus. A descendant of the brother of the great-grandmother threatens to disclose the birth certificate of the pol's great grandmother that has the letter "N" under "race"... and some unaltered photographs of what he presents as some "Cherokee princess"* that he waxes rhapsodical about. The blackmailer asks for $20K every year, and the pol sends amounts of $9.8K twice a year as cashier's checks from the bank and another $400 as a money order paid for in cash.
The blackmailer gets greedier, demanding $25K, and the pol then sends cashier checks for $12K and a money order for $1000... not recognizing that the amount for which the Feds look is not adjusted for inflation. The pol gets caught.
The Feds see the blackmail as a worse crime than the payoff, and give the pol a deal -- testify against the blackmailer in a federal court for tax fraud or money laundering even if such implies having to admit to failing the one-drop rule. Having to admit that he is one-eighth black is far better than ending up with some tough black guys who dealt drugs or robbed banks who now reside in a federal penitentiary.
In the case of Dennis Hastert, it seems that the reality covered up is worse than the payoffs. Surely the child sexual abuse would now be sloughed off in the courts due to the statute of limitations. But money laundering -- if Hastert can't be nailed for the child sexual abuse he can be nailed for money laundering.
...I suspect that the victim was caught first for either money laundering or tax evasion. Of course he cut his deal to save himself from some federal time and some confiscations. I don't know for sure, but that is how things can work.
*The Cherokee had no nobility, so the story of his grandmother's origin is a sham.