Is the customer first?

Today I went to visit a friend who have just opened a new restaurant-bar at Merida. It has just 2 days of commercial life.
By the way, when I was walking through the parking lot, a lady went out of the bathroom and told me before entering the facility:
“This site is awful. Have been here before?”
I told her that she was right and why does she was upset. And then she said:
“The beer is hot and my husband does not feel comfortable”
Finally I told her to ask to speak with the bar’s manager and let him know her situation. And it ended there.
As the bar’s manager is my friend, I told him that I wanted to share something with him. Then I spoke with him and I shared the experiencie I got with his customer, so he can anticipate the customer and ask them the classical phrase “Is everything ok?” or “Are you having a good time?”.
Then he told me:
“You know man, there will always be a person who you can not satisfy”.
I didn’t want to let him throw to the trash-can the opportunity to save a client, that’s why I encouraged him and insisted in anticipate the costumer’s complain.
The important thing is to exceed expectations. If the woman wanted a cold beer instead of a non-desirable warm beer, just give her what she wants AND a little bit more, like a bonus appetizer or a paid-by-the-house desert. It is better to spend 2 dollars, than loosing a client forever.