The US Bureau of Labor Statistics says 55.7% of all workers in the US are paid by the hour.

I don't know how that compares to the rest of the world, but I would think that this alone would justify the need for having an hourly-based salary package option.

On that topic, the use of "salary" in "salary package" is not correct. Salary specifically refers to periodic pay (almost always annual) that is independent of hours worked. When pay is determined by the number of hours worked, it is called a "wage".

Both salary-based and wage-based schemes could be called "pay" or "compensation", but they're not interchangeable with one another. What People calls "salary package" should be replaced by "pay package" or "compensation package" and allow for the payment of employees via wage.