"What would happen to businesses if everyone had unlimited cash?"

Business would have some troubles. If the consumers had unlimited cash there would be no labor because people would not have to work. Consumers may be able to buy more products but a the same time their would be little no labor force to make products. Businesses with products that need a lot of time and effort to make e.g. blown glass, custom guitars could lose workers if the workers do not truly love their jobs. That would leave the production to a smaller amount of people. People who have lower less important jobs in businesses wouldn't have to work so the might quit, leaving some of the little yet mediatory work not finished. But most importantly, money would be no object and in a society where there is unlimited cash money would end up being completely useless.