some of them are just scams trying to sell nice cars, at cheap prices and if they do not "block" those plates then the people would realize it's something odd on the sale.

I have even seen same add, same plates, different owners, different prices...WTH??

And yes you are right if I am going to buy a second hand car upon showing to the traffic dept I will ask to check for fines, settle them immediately and then we'll see.

Regards!!