Most of them have the mentality of replacing vs. repairing. Think about it, you buy a new part, get the warranty behind it (a year) and they do not worry about it. They don't care how much it COSTS YOU. They are worry about their pocket, not yours. Can you blame them?
Lubing the speedo cable may be a DIY'er fix or an independent trying to save you money.
BTW, I did not notice what car you have but, the cable in my car is less that $40 (depending where you buy it).