Of course, Moby did not act nicely towards Travis out of the kindness of his heart, he only did what benefited him. He could not care less about anyone that was not part of his close, inner circle of friends.
Moby's true intentions were to keep Travis close, on a leash as his loyal dog, a pawn that he could use to extract valuable information from the Zexis clan without turning him into a demon, reducing his chances of failure and removing a great deal of stress in the off chance that he is caught by them or betrays him, which would lead to his secret being completely exposed.
If they found out that he and Moby were not on good terms, they might replace him with someone else, or, even worse, kick him out of the gang for being useless or for wasting their time, both options being something that Moby did not want.