"but the human eye can only see 30fps!"
The sensitivity of the human eye goes way beyond 30fps. Studies have shown that viewers can distinguish between modulated light and a stable field at up to 500 Hz. As a more practical example, many reviewers have noted that the new iPads' 120 Hz refresh rate has obvious, visible benefits for scrolling and animations.
In a 60 fps stream, you can insert one image that is way off from the rest, and it will be detectable. You have to go around 100fps for that "blip" to go unnoticed.
So when it comes to transitions, high frame rates actually do matter, as that makes the difference between something smooth & natural, and something that appears jagged & visually annoying.
But for gaming, anybody that can't tell the difference between 30 fps and 60 fps is blind. I have a 144 hz monitor, and I can certainly tell the difference even between 60 fps and 144 fps.
The UFO Test [0], while contrived, will show you the difference. If you have a 60 hz monitor, it will show things moving at 60 fps and 30 fps (And 15 and 7.5 fps, if you want). If you have a 144 hz monitor, it will show 144 fps, 72 fps, 36 fps, etc. The difference is clear, especially if you're following the UFO with your eyes. The higher framerate is less blurry. In games, this can be huge.
If we're all formal all the time, it's going to be hard to welcome new people. It's important to make sarcasm obvious though (because it's difficult to express), so that newcomers who may not know that this is ridiculous can feel "in" on the joke, while learning something, and not being embarrassed.