What is vain about it?
It is simply a prayer to dedicate prays, works, joys, sufferings, objects and people to God. It's not a good luck charm, it's a dedication of successes and failures.
The problem with Babel wasn't that they were building a tall tower, the problem was that they were attempting salvation without giving God His due.
I appreciate the question, Wabbi. I even appreciate Slum's observations, even if I disagree. It gives me the chance to enlighten the subject.