It's supposed to be that the American League teams are the ones that benefit from playing at home in the World Series, at least when it comes to constructing a lineup. They're the ones who need a DH for most of the 162 regular season games, whereas the National League teams have to scramble and make do to fill a position they don't have to usually think about.
The St. Louis Cardinals, though, are one step ahead of most NL teams. They signed a DH to play right field in the offseason, so now they can put him back at DH for three World Series games. Pretty savvy. Now that they survived 125+ games of Lance Berkman's wonky right-field defense this year, they're pretty well set up for the next three games.
Is Skip Schumaker healthy enough to start? Don't know, but it wouldn't have made a difference tonight, as Theriot or Nick Punto probably would have been in against Texas lefty Matt Harrison anyways. Craig moves up to the #2 spot against the lefty -- with previous lineups against lefties, Jon Jay would remain in the #2 hole. With the DH in play, though, he moves down all the way to eighth.
This isn't the typical NL team, like the Giants of last year, who put Aubrey Huff at DH to get Travis Ishikawa in the lineup. The Cards actually have more good hitters than they know what to do with, and the DH helps them solve that problem