I call BS. It would reflect in our culture if it were important. Easter is nothing more than morphine drip to assuage our guilt before God.
No, to correct you, Easter is when Christians REMEMBER the greastest miracle ever done by Jesus, by rising from the dead.
There are droves of Christmas and Easter only Catholics (and I assume protestants as well). It always amazes me, on those days, how many people I see at mass that I have never seen before... and I usually recognize about 80% of the people on a given Sunday. The good thing is usually it inspires a handful to come back to communion regularly.
If you are referring to the thousands who never attened church other than Christmas, Easter, for weddings and funerals, I agree.