I feel a lot of people who can't see the difference just don't know what they are looking for.
Example, When playing third person shooters rotate the camera quickly, the refresh rate really effects how many frames you see of the landscape wizing by. A higher refresh makes it so I am able to pick out details easier, doesn't matter what the numbers are to me, higher is better.
I'm not one of those people who can't stand 30fps but I am a huge fan of highFPS. I'm currently replaying mass effect trilogy on my PC, with the high FPS. I'm constantly blown away at how lifelike the presentation becomes. when I'm capping above 60fps it's like I'm watching the coolest marionette show ever, like it's right in front of me. my brain doesn't get tricked like that with 30fps.