Sure have. I probably talk them out of grout sealing the most. Seems like most folks here think sealer keeps grout from getting dirty. I tell them how it works and more frequent cleaning seems to be the best way to go many times.
Lots of times for small water losses, WDR work is expensive and when it's small enough for the homeowner to handle themselves, I'll ask them if they would like to.
I'll even try to help them step by step and tell them to call me if the have any problems.
Unfortunately a lot of them still want us to do it any way, but as long as they know the rate I don't feel bad.