Walt did indeed walk, he and Roy learned years before to maintain total control of his properties, real and intellectual. The Busch family wanted not only to require beer in the proposed St Louis park but told Walt it would be Bud and only Bud served. If Walt didn't agree, they were going to stop the park by their local political connections. Walt wanted a family park and not another park with drunks around, That was the standard of the day and he was not going o have it.
Walt stood and walked away from the table after being told that and never came back.
This had little to do with money as the Busch family was not putting up any money for the park.
This still comes down to why alcohol in the MK...............anyone can get alcohol anywhere else in WDW, there is no need for it in the MK.
AKK
And that's the thing. The "need in Magic Kingdom". The OP suggested only at dinner in table service restaurants. Not kiosks, not red beer cups. I don't think there a suggestion of "need", I think there is a suggestion of "want".