In the modern corporate world that leadership has entirely insulated itself from customer feedback - if it was plausible to voice your opinion through more appropriate channels I'd advocate for that but many companies have purposefully shut those channels down.
What is the better option to pass along that message than modestly increasing retraining costs for that position?
I treat service workers with respect, personally, but I am struggling to see what other venues of communication are still available.
1) Stop using the service.
2) Directly email them anyone who might have some say in the matter.
3) Make public posts on social media about your position.
You still may not get heard, but all of these have better odds than complaining to the front-line service workers.
Like I said in my other comment, this is missing the point. This approach won’t be effective. Nothing is actually being communicated to the people making decisions. The difficulty in finding another more effective approach doesn’t change that fact. If you feel passionate about this issue, you should try some of the suggestions by the other commenter.