What is the logic of storing XML in a Database?

I see people putting XML documents in databases. Why do they do this, what is the logic behind it? Why not just put the data into tables? Why are the standards committees going along with this (XML SQL/ MED)? Why don't people just use tables to store the data thusly:

CREATE TABLE FOO_CUSTOMER
(

name VARCHAR
address VARCHAR
key INT
);

why are they doing this:

CREATE TABLE BAD_XML_CUSTOMER
(

 customer_data XML

); Received on Tue Mar 27 2007 - 00:15:42 CEST