This is pure BS.
I have worked in restaurants from the age of 12 (family business) and have managed multiple restaurants and bars.
Wait staff takes orders for food - the menu is a starting point.
Have you never eaten in a restaurant that does not have a menu? They ask you what you would like and you tell them.
I have fired many wait staff who refuse to comply with the wishes of the customer. Make the customer happy and they come back. I never allow staff to run-off my customers.
NEVER, EVER tell me I can't modify what's on the menu to suit my tastes and needs.
Don't tell another poster not to order a Cobb salad because you don't think they should ask the restaurant to 'hold the avocado.' If the business does not acquiesce to the request - another restaurant will gladly do it and have a new, happy customer.
BTW, I do not eat fast food - ever order a burger in Canada?
Yes, and that is a completely different business plan. I would expect special orders in a reastaurant like you have described because every order is a special order. But special orders in a fixed menu restaurant is a PITA. We will try to acccommodate, but we don't like doing it.
If the business does not acquiesce to the request - another restaurant will gladly do it and have a new, happy customer.
High maintenance customers are generally money losers in all but the most overpriced, trendy restaurants that exist primarily to serve the powerbrokers and beautiful people, and their groupies. In my experience, many special order customers also complain the most, tip the least, and hang on to the table while others are waiting as if they rented it for the night. I wished they would take their business someplace else, but for some reason they kept coming back.