Ultear might be working for the good at the moment, hunting down villains, but she has certainly lost none of her cruelty; humiliating Jellal, and all of Fairy Tail in fact, in front of thousands of people is nothing but sheer evilness. There should have been a better way, even an instant KO would have been far more preferable. At least that way it would have looked like Jellal's grand spell backfired or something.