The correct approach is to make sure it doesn't happen incorrectly in the first place, and that it can be resolved quickly and easily if it ever does.
There is no more than 100% wrong. Saying it is 1000% wrong implies that you are arguing emotionally, not rationally.
Rationally, it doesn't matter how google reacts to their non-customers. There is no obligation to treat them well. The correct approach for non-customers is to either become a customer or to switch to another provider.
If somebody is wrong it is the non-customers who could fix the situation. Their unwillingness to change email providers is what enables google to keep on providing that bad service.