I would give a 5% tip as a sign of disappointment with the meal.

That is still very generous of you. For me, disappointment would mean no tip at all. Giving them a tip for something disappointing will relay a wrong message that they somehow did good.

their TV show was more important than their customers

I feel you. Countless times I have been into this situation not only in restaurants but in different merchandise stores, even in malls. While I do not agree to the saying that "the customer is king," I still wish that all business folks would understand that their customer is the life of their business.

I came across your article through @dollarsandsense who featured it on his post as an entry to the Pay It Forward Curation Contest. The contest is open to everyone so you are welcome to join.

You can also join #ccc for Guaranteed 👍 Daily Income 💵 and Payout 💸 for Newbies (2.0) 🐟 🐜 🐛 in #ccc 👣 and Follow 👣 the Honor Code 🏅 - the Creed (Conditions and Limits Inside) AND the latest update <<< please click to read.