Ultimately, makers and dealers selling knives makes a good show. In the short term, it means that the hall is full of enthusiasts, buying knives, and happy, and the people behind the tables are making money, so they're happy.
In the long term, good "money" shows will attract bigger names, the table holders will bring larger, better varieties of stock, and bigger crowds will be drawn to the names & knives.
Although most of my buying is done to order, I try to spend some money at every show I attend, even if it's just a token, like a sharpening stone or a lanyard. It's a karma thing...