But how was he a bad businessman then?
Well, holding up a promoter for more money, minutes before bell time isn't a good business move. Not to mention, accepting payment from an indy promoter, only to no show the event with no explanation isn't a good business move either.
Personally, Warrior profited from it but all it does is further the perception that he was an egomaniac, regardless of how intelligent and down to earth he is in real life.
But at the same time, all can be overlooked, as Warrior was brought back twice. And IIRC, he held up Vince for more money again at Wrestlemania 12, although not to the extent of Summerslam 1991, as well as making various demands as to how he would be portrayed in his match with HHH.
If those aren't bad business moves, then HBK refusing to job, HHH bitching about jobbing and Austin walking out twice aren't bad business moves, as you can look at them in regards to that particular person protecting their image and recognizing their true worth and potential. Still doesn't make it a good decision and gives the idea that they portray themselves as bigger than the business that created them.