My last point was buried in my earlier post, so I will stress it again. When Walt died, anyone could pay $2 and walk right into the gates of Disneyland park. You add alcohol to that and you can easily attract the wrong clientele. It is completely understandable that, with that pricing model, why Walt would not have wanted alcohol in the park at that time. If you were visiting the park and putting down $$$ to enjoy attractions with your family while others were there to consume alcohol and engage in mischief, it would clearly not be a great experience.
We are in a very, very, very different era in Disneyland's timeline now. People are paying hundreds to enter the park and thousands to stay there for vacation. Surely, when Walt made this decision about alcohol, he was in a very different mindset about Disneyland and it's customers.
If you want to hold on to a decision he made back then, you are completely ignoring the 50+ years of evolution the park, its customers, and its status as an entertainment/vacation destination has seen.