It's unfortunate that businesses do this. Starting off a relationship with a new customer by effectively saying that your pricing isn't 100% honest seems like the wrong way to go about it.

I want every one of our customers to be 100% confident that they are paying the same price as anybody else on the same plan. In our case, I've even explicitly refused to do any deals or promotional discounts. This keeps things simple for us to keep track of as well.