Part of the reason is that people model the behaviors of others; which includes mimicking them and using common vocabulary words and phrases. This, and thinking in general, takes place on an unconscious level. Deeper thinkers think about what they are thinking about (called metacognition), and are less susceptible.
I've observed, and been annoyed by, the excessive and inappropriate use of the word "amazing" for a while now. When you become consciously aware of it, you will see that it has reached epidemic proportions. My solution? Education.
Since fewer people are reading these days, and "skimming" is at an all time high, I recognize that opportunities to augment one's vocabulary do not abound for everyone. So here is a list of alternative words that can - and should - be used in lieu of "amazing," unless, of course, something is truly amazing - like being a runner in the Olympics when you have no legs.
First, the definition of a·maz·ing/əˈmāziNG/
So, according to Merriam Webster, everything can't cause great surprise; though small children can be genuinely "amazed" at things, but as they age, that amazement subsides, due to habituation. And as for being startlingly impressive, e.g., "Last night he was soooo amazing"....that's comparatively speaking. It says more about what you haven't experienced up until that point, than it describes the experience...whatever it may be.
Try these adjectives instead: extraordinary, exquisite, fascinating, remarkable, spectacular, sublime, superb, titillating.