The reason a lot of people do not appreciate a classic cocktail in most establishments is more than likely it was made poorly with a sweet and sour mix rather than fresh squeezed fruit. This mix is nothing but high fructose syrup with artificial lemon lime flavoring, and preservatives which is not healthy. So if this is so bad, why to most "bartenders" insist on using sweet and sour mix?
Using sour mix can be mandated by management or the inexperienced bartender might give you the "deer in the headlights stare" and have no answer because they don't know any better. Sweet and sour mix is cheap, keeps well and is a short cut rather than using fresh ingredients and it doesn't make good bartending . It also alters the taste of the cocktail so that most patrons will think they don't like a certain drink rather than the bartender taking an extra few minutes to squeeze fresh lemon or lime juice.
If you look in older bartender books from the nineteenth and first half of the twentieth centuries such as Old Mr. Bostons guide 1935, The Savoy Cocktail book or Patrick Gavin Duffy, it always states, use an ounce of either fresh lemon or lime juices. A well crafted drink need not be complicated but fresh ingredients are always required. Next time you're at restaurant or bar insist that the bartender use fresh ingredients as opposed to sweet and sour.