As the Captain receiving the reports from several CM's and noting that one has a very high offload request compared to others, continuing to just offload at that CM's opinion could leave you open to disciplinary action (for not bringing the CM's high incident rate to management attention and loss of customers as a result).
I dont think that is what is being suggested.It also assumes that a particular Captain is flying with a particular CM (who uses offload as a regular event) frequently enough to notice a trend. I probably fly with any individual CM no more than twice to three times a year. If a CM requests an offload there is usually a good reason. Most cabin crew and pilots just want to get through the day with a minimum of fuss and don't take the offload option lightly.