Telling the owner quietly beats roasting them publicly. One fixes the problem, one just feels good.

Public criticism hands you an audience, agreement and a quick hit of satisfaction, and it rarely changes the thing you were complaining about. A quiet word gives the person a chance to fix it without defending themselves first, which is when people actually listen. The question is whether you want the problem solved or want to be seen objecting to it.

Go to them first and keep it specific and short. Give them a real chance to respond before you say anything wider. If they do nothing with it, going public afterwards is a different and much fairer act.