Module Sellers on Ebay removing serial numbers

For whatever reason, there is at least one seller on Ebay that states he "removes the serial number from the modules by grinding them off" prior to sale.

I can think of a number of reasons to do this, all of them are bad

Do not buy modules with no serial number, in fact, insist on knowing that info prior to purchase.

It is a federal felony to knowingly remove, obliterate, tamper with, or alter an identification number for a motor vehicle or motor vehicle part

Penalty is a fine or 5 years in prison or both.

Aside from the issue that they could be stolen, I think they are being obliterated to prevent the buyer from knowing how old they are, and of course they cant be tracked back to the original vin by toyota or law enforcement, which is why it's illegal to do it.