Some bring up the selfishness of it. Which they have a point - why should any1 have to give over stuff for free? (Welfare!)
OTOH what the hell? It's cheap (I bet I spend less on candy for H slews of kids then I could on Christmas cards alone). And it's kind of cohesive - "we all do it" all over the country and we actually interact w/others in the public over it.
I spent about four hours carving pumpkins yesterday, for one night's use. How selfish is that? Actually, as a kid, my avarice meter was a lot higher on December 24 than it ever was on October 31.