Sniper Wolf's Shot

[black king]

So I was watching someone do a playthrough of MGS1 and had a question about Wolf. When she first reveals herself after the caves, she has Snake in her sights perfectly but then intentionally switches targets to Meryl to use her as bait to lure Snake out of cover. Why do that when she already had her target in sight? She later said she doesn't kill for pleasure or sport so why shoot Meryl at all? I know the answer is probably "so the rest of the game can happen without it being an escort mission" but is their anything more here?