When we disable V-Sync it is not to get a higher monitor refresh rate, my 60Hz monitor is maxed at 60Hz no matter what, it is a hardware limit.
Disabling V-Sync shows what the max FPS your system can handle if it had the hardware(monitor for example), but mostly it is an indicator for us of how strong our system is.
Imagine an average case in a game(any game), and you see the FPS at 180. That indicates that when your game gets really busy(like a big battle) you will have a good chance of still having over 40 or 50 FPS,because you have a huge buffer of about 200%(60 to 180).
Now if for the same average case in that game your max FPS was 70, and you got to the graphically intense battle scene, you might be lucky to get 20 FPS.
The above numbers are all exaggerated examples to state my point

(because every game is different)