The one issue here is that in many industries, the use of "vacation days" is, per the labor contract, required to be scheduled in advance. Often quite some tim

The one issue here is that in many industries, the use of "vacation days" is, per the labor contract, required to be scheduled in advance. Often quite some time in advance. Which makes use of "vacation days" for unexpected illnesses (went to bed last night and felt fine, woke up this morning to fever and chills) difficult to impossible if the requirement for "advance scheduling" is actually enforced. In many jobs with separate vacation and sick days, the vacation days still require the "advance notice" for scheduling, but the sick days do not require that one know, days in advance, of an unexpected illness. That gives the employee a few days that can be used for unexpected things, and the employer some assurance that a maximum of X days of unexpected outages will occur per employee. More often than not, the "only one type of paid leave" comes attached with the "requirement for advance scheduling" of those same days, which does not provide for the unexpected illness situations.