I'm struggling to find a good answer as to why a player would not be credited with a stolen base under the official MLB rules. It seems to me that most indifference calls are made when the defending team is far ahead and is wanting to avoid errors more than record outs on attempted stolen bases. This seems like a pretty weak argument, so I'm looking to see if there are others.
Here is rule 10.07 talking about DI (and linked to above):
Rule 10.07(g) Comment: The scorer shall consider, in judging whether the defensive team has been indifferent to a runners advance, the totality of the circumstances, including the inning and score of the game, whether the defensive team had held the runner on base, whether the pitcher had made any pickoff attempts on that runner before the runners advance, whether the fielder ordinarily expected to cover the base to which the runner advanced made a move to cover such base, whether the defensive team had a legitimate strategic motive to not contest the runners advance or whether the defensive team might be trying impermissibly to deny the runner credit for a stolen base. For example, with runners on first and third bases, the official scorer should ordinarily credit a stolen base when the runner on first advances to second, if, in the scorers judgment, the defensive team had a legitimate strategic motivenamely, preventing the runner on third base from scoring on the throw to second basenot to contest the runners advance to second base. The official scorer may conclude that the defensive team is impermissibly trying to deny a runner credit for a stolen base if, for example, the defensive team fails to defend the advance of a runner approaching a league or career record or a league statistical title.