Advent—does it matter?

I've had a lot of discussions over the past week about Advent. Mostly because I'm brimming with delight and bubbly joy at the sheer thought of the season. This tends to bewilder people.

"What is Advent, anyway?" most people ask. A few have related stories of how terrible Christmas was for them in childhood—December was a month of stress and family discord. Others had churches where candles were lit, for reasons mostly unclear. For very few people does Advent, as a season, register as even mildly important.

Of course this goes for the entire Church calendar, which was somehow ejected from the Protestant church along with the papal bathwater. Many evangelicals turn up their nose slightly at the mention of Lent (abstaining? sounds like legalism to us!), and know Christmas and Easter only as single-day holidays, marked more by their secular dressings (Black Friday, Easter eggs) than their liturgical settings (Advent wreaths, Lenten fasting).

Does this forgetfulness matter? I think it does, for a few reasons:

I'm hesitant to reject traditions too quickly. By all means let us hold to what is good and reject what is false. And, yes, let's breath life into tradition instead of letting it get stale. All the same it seems unwise—if not arrogant—to assume that what fed the church for 1500+ years doesn't concern us.
We desperately need every tool available to us for remembering and living inside the Gospel. As a professor of mine said, "Any stick to beat the Devil." The church calendar is a mighty useful stick.
We are going to live in some sort of calendar, regardless. Do we really want our primary understanding of time to be an academic, financial, or civil calendar? Are the seasons going to be marked by our patriotic holidays and our big sales, but not by the life of Christ?
It takes time to absorb weighty, life-altering truths. It seems unfair to expect anyone to ramp up to the mysteries of Christmas and Easter in a day or two. Churches do their people a disservice by sneaking up to these celebrations without word of preparation.
Why on earth would we not want more time to celebrate? Am I missing something? If Christmas is good for a day, why not eight? If we're really excited about Jesus' return, why not take four Sundays of the year and remember to long for it? If we are truly sorrowful over our sin and longing for healing, why not focus on the Cross for 40 days?