For someone at the sixth level of Nirvana Realm, changing one's appearance is an easy task; anyone can do it.
So, Ugly Bull's hideousness was something everyone knew he was putting on deliberately.
However, no one would mind such a deliberate ugliness, since everyone out in the world has a side that's unknown or hidden to some extent!
The Luo clan naturally could tell Ugly Bull was intentionally disguising himself, perhaps to avoid enemies or just to blend into the crowd for some twisted amusement.
But as long as he doesn't bother anyone or interfere with anyone, no one would expose him or care!
If you want to disguise yourself as ugly, that's your own business; it doesn't matter to others, does it?
However, Miss Luo was a woman who valued loyalty and knew how to repay kindness. After giving Yusuf Zuck the Fate Fruit, she questioned why he was disguising himself as ugly.
