That can be a two-edged sword. Yes, the people that stay and cover other positions definitely deserve more compensation, but the danger is that the management will make the added responsibilities the norm for the poor employees that are stepping up. Bad Management can also use that to justify saving payroll by not filling positions quickly or even getting rid of some positions outright.
If the organization doesn't identify and fix the undelying issues from the start, it can be difficult to change them down the line, which will only increase turnover.