The title for this thread is objectionable. the OP has the right to question, not declare it shtus out of ignorance.
Here’s the reality. There may well be kabalistic aspects to the practice/minhag. I cannot address that (out of ignorance). But the upsherin is a milestone of chinuch on “peyos harosh”. Aside from the lo saaseh of cutting the peyos, there is the initiating of the tzurah of a Yid, having peyos. This hopefully remains with the child for his entire life, and this is worthy of a celebration. The minhag is actually referenced in quite early writings. As with many things, it was primarily a minhag adopted by the chassidishe community, but has spread to the yeshivish communities as well. The typical ceremony is the learning of aleph-beis, a valuable piece of chinuch. It is worthy of a celebration. One commenter was appropriately irritated when witnessing the purchase of an expensive dress for the occasion. True celebration involves so much else that the obsession with fancy clothing is a distraction, at the very least.
I hope the mods can fix the heading to be more informative and inquisitive, not degrading and disgraceful.