People have different minhagim.
In my family we wear white kippot only for the Yomin Noraim. The exception is for the chassan on his wedding day (with its fast, similar to a Yom Kippur Katan).
Over the years, at weddings and B’nai Mitzvah I (and my father before me have amassed a large collection of kippot that are stamped inside with the name of the celebrant(s) and the date of the simcha.
On Pesach, when guests arrive to our seder, they may often find a kippah from their, or their father’s Bar Mitzvah/wedding attached to their place-card. It brings a smile to their faces as they don this special Kippah for the evening.
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