It's hard to see what damage could be caused by not checking docs.
Some people who aren't frequent flyers with another airline get Gold status and then spend some money? Or they get status and then don't use it?
Since you can't churn it into status with another airline without flying I can't see a downside for SAS.

The damage may be psychological, because the easier it is to get, the less you will value it and the less likely you are to spend money.