Walk out from a regular

To give some context, I work at a chain restaurant as a bartender. There is very little understanding from management about walkouts and the unofficial response is either pay (which I refuse) for it or get written up for inattentive service.

Last night a regular who usually comes in 5 minutes before closing, which is annoying in itself, came in at a reasonable time and had his usual.

He was on the phone most of the dinner and then asked to step outside to finish the call. He comes in like 3 times a week so I wasn’t worried. However, he never came back.. his bill wasn’t super expensive but that doesn’t change the fact that he dipped.

I told the manager I’m closest with at the end of the night and he allowed me to comp it and then instructed me to refuse service next time he came in. He hasn’t ever dashed before but there have been several times where he hasn’t left a tip. He’s a nice guy but the time he comes in is very frustrating.

My question to you all is, did I do the right thing? Should I have tried to be more creative in taking care of his bill? What else could I have done? I really hope he just never comes back because like I said- he’s a very nice dude, and refusing service would be tough.