You cannot block Google Voice CallerID.
You could set up a second Google Voice account and not assign an incoming number to it. Calls placed from that account will have a CallerID of : (760) 705-8888
Quite true. However, you can also go into GV and block phone numbers, so even though you divulge your number to them when you call them, if you don't want them calling you you can block that. I do that immediately after receiving a political call or charity or other bothersome telemarketing call.
Of course if they are spoofing the number "This is Judy from Duct Cleaning Services" or "You have won a cruise", you have no recourse except to swear at the recording and throw the phone through the window...