"Almost definitively". So, you are not talking from factual experience, but from your own perception of what the client will do in the future. In my experience you are totally wrong. If you do a good job, they will not only praise you to high-heavens, but they will refer other people to you as well, and yes, they will come back for more.
A frum guy at our client didn't shake hands with someone on my team. She was very slighted. I needed to explain it to her but regardless of any explanation, she was still hurt. This was the flip-side as it was our client, but team member was hurt nonetheless.
The "shaming of others" claim doesn't sit right with me. Are you careful about not shaming others in other circumstances?
I seriously hope this is a joke.