No, I have never asked for a "free upgrade". If the carrier wishes to grant me one, of course I do not refuse. Like many frequent travellers I take advantage of FF programmes, and reap the benefits therefrom.
I am in business. I operate that business in order to make money for myself, to be able to reward my employees, to develop the business for the future, and to generate reserves against unforeseen circumstances. In order to do so, I charge a fair price for the services I provide.
I do not hand out my company's services for nothing to any Tom, Dick or (in this case, it seems) Harriet who has the effrontery not only to ask but to think it a right to which they are somehow entitled.
Air transport carriers are in precisely the same position.
Does that explain things clearly enough?