Why can’t Bars make a Decent Drink?

I like my cocktails: the original cocktails, made per Mr. Boston’s guide. Many of the drinks, like whiskey sours and margaritas, are very strong. I make a whiskey sour with 1½ ounce of rum, 1½ ounce lemon juice, simple syrup to taste and a bit of egg white if I want froth. Shake the living hell out of it and serve. It’s delicious, but it is strong.

I go to any bar and get a whiskey sour and get 1 ounce of whiskey, 4 ounces of sour mix. It’s unpalatable. I know that restaurants/bars have to measure the liquor, but they are so obsessed with giving you a large serving that they ruin the drink. I would rather have a smaller drink with the correct proportions than a larger drink that tastes like lemonade (if I’m lucky). Anyone else feel this way?