Why is preschool more expensive than college?

This week we looked into preschools for our youngest son.  Our favorite preschool comes with a hefty price tag of $320 dollars a month.  This isn't a snobby private school, just a normal preschool open to everyone.  It's only half day, and four days a week.

That's $1280 a "semester" for a toddler to learn his letter sounds and count to 25.  I just looked at the local community college and it's only $1140 per semester for a full-time student.  Now granted this is a community college, and regular colleges are about twice that, but it's still an accredited institution with a qualified degree!

The fact remains that I can give my child a college education for less than it costs to send him to preschool.  Does this seem right?  Have you had the same experience?