Danny could admit that pretending to be a "regular ghost" was pretty fun. He could hide in one place and scare people who were waiting for an open door and a creepy laugh.
Honestly, Danny could do a lot more than that, the ghosts people believed in were nothing like the ones he knew. He wondered if there were simply different types of ghosts, or supernatural creatures; it was quite likely, considering that the ghosts of the Realms weren't even of the same dimension so it wasn't a fair comparison.
Anyway, the halfa had spent a couple of days "haunting" Gotham. The place was too leggy and they needed a little excitement in their lives. Of course, this led to some rumors about a spirit suffering or something similar, he didn't really care.
The "heroes" of Gotham didn't seem to share his opinion, going through all the places that had been "attacked" (they were just jokes) and looking for some explanation before calling Justice League Dark, Danny had fun scaring them a little in the process.
But he wasn't too interested in being exorcised, banished or whatever they did with rebel ghosts, so he settled on a mansion that was too big for its few inhabitants. Scaring billionaires was almost therapeutic, although the butler didn't seem too impressed by his (minimal) efforts.