Well, if everyone was to behave like that, we wouldn't have any Growlers in the first place.
I've been in the opposite situation - had a 'Growler' for a boss, moved company, got promoted, and sat on the interview panel when, low and behold, 'Growler' walks in applying for a job. Immediately started acting like we had been best buddies previously.
Needless to say, he didn't get the job.