You are entitled to a full refund of the seat fees if you wish. But, seat assignments are not guaranteed, so nothing beyond that. I don't think that there will be any argument about a refund as opposed to a voucher or that OP will experience a parade of horribles. I also don't think that any LX "file" is affected if a chargeback dispute is initiated, but some card issuers do frown on those who make excessive use of the device when not even an attempt at a refund has been made.
Most -- although not all -- carriers require a request for a refund because many passengers, I am one of them, do not want a refund immediately as seats often open up again and it is nice to have paid for them and simply be able to hop into them without waiting out a transaction.
I suppose that the answer to your question is yes, this is fairly standard practice, at least pre-flight.