In my 20 years in the restaurant business, I saw my share of customisation requests.
Some were sensible, others bordered on the ridiculous.
It is one thing to accomodate a customer when things are slow, it's another to put the kitchen in the weeds in the middle of a Saturday rush.
Maybe it comes down to managing expectations.
Some restaurant managers are not very good at managing these or depending on the place where they work, they might be afraid to get their fingers slapped if they say no to a request...
Victims of the adage 'the customer is always right'.
I served a family who brought their own gluten free pasta with them.
I saw others bring their own soft drinks with them and think nothing of putting them on the table and finishing them in the course of their meal.
A few of these memories where brought back to the surface by Have It Your Way? Puritan Chefs Say No Way (NY Times, March 4) by Diane Cardwell.
In java land, she notes that Cafe Grumpy says no to espresso to go.
David Chang take in the article brought this question to mind.
Would you go to a Vegetarian Restaurant and ask them for a Meat Dish?
In a more general sense it comes down to showing respect for what the chef and his team have created as Elizabeth Andoh highlights in Kansha.
Why ruin your duck or lamb with ketchup?
(* illustration is photo of Cafe Grumpy, from their site)