They don't do weight checks in the Netherlands. The process is super efficient. They have certain reasons to have a human check out your load before accepting payment (weight might be a part of it? But probably not). You must scan your receipt to leave. So far as I understand, I think it works really well here. They probably catch enough serial shoplifters to make it work.

My guess is that the "featurism" of the weight check was promoted so much that they feel weird just relying on the tendency of people to be honest. But people do tend to be honest (especially when there is a small chance of being caught)