Growing up in rural Massachusetts, Judaism held a much different context in my life than it does now. Until college, I did Judaism, mimicking the motions of being a "good Jew." I didn't combine milk and meat in my house because my father told me not to.
There are many elements which make the High Holy Days a unique experience. Often, congregations swell to double or triple their usual size, the musical settings of even common liturgy are different, and some might alter their dress by wearing either traditionally all-white garments or more formal wear than they would sport on Shabbat. Some congregations even have unique garments to dress their Torah scrolls in white.