I think Americans have a twisted viewpoint on alcohol, from those who are judgmental and say "if you can't have fun without booze you are an addict" to those who think fun is to drink as much as they possibly can, vomit, and start over.
I was thinking this while perusing this thread, but I didn´t want to say it ´cause I´m not American and I don´t wanna be
that person, but you´re the one saying it, I´m just agreeing! LOL
Joking aside, I do think that where I come from drinking alcohol is a bit more accepted, and when it´s done socially is not that big of a deal, even in front of kids. My parents and the rest of my family always drank beer and wine around me and my cousins and it was never frowned upon - we knew it was "grownup beverage" and we couldn´t have it. Then again, in my country alcohol drinking minimum age is 18 and I had already had some beer and some wine by 16, so...
Also, I do believe that experiences may vary: I know people that absolutely loathes drinking, even if it´s socially, and judges people that get a little more tipsy, because they had bad history of alcoholism in the family.
Speaking for myself: I "discovered" WDW as an adult (was 28 on my first visit), I don´t have kids and enjoy drinking socially, not only to get a little more relaxed and cheerful, but because I like the taste of the beverages - especially wine. Epcot is my mom´s favorite park because of all the food and drink options and we always drink around the world. Obviously we are reasonable people and we know how to behave. If people are just having fun, let them. I do believe the tshirts are a little tacky and I probably wouldn´t wear them, but they are just puns. They are really harmless. I don´t have kids, but I can´t see how seeing a Disney princess with red bloodshot eyes is gonna convince a child that drinking is good/cool. In fact, if I saw that when I was little, I would probably be more scared of my favorite princess looking like a zombie monster than being seduced by drinking lol.