If you publish any kind of price, that affects your negotiation options if you want to do individual pricing/haggling for each customer.

Also, a multitude of factors affect the 'true' price including various risk estimates of your company, and it would be counterproductive to say "factor X, as measured by Y, gives you a price increase/decrease of Z", as that would just result in gaming the measurement and misleading about the nature of your business.

I think it's excusable for a relatively niche B2B service where there's likely a huge variation in the size of their customers. Price discrimination is hard.