It depends on which blank you're talking about and which model was bought with which options. It's early in the morning so my brain's not in gear yet but one example is the windshield wiper heaters.
Most common blanks are for seat heaters, early models also had a button to turn off RSCA, not needed with different programming in 14+ I believe. There may have been a button to turn off sonar sensors in some models.
It’s cheaper to make everything the same and fill in the extra holes with blanks than it is to make a new dash for the different trim models. Limiteds have parking sensors, there used to be a party mode button, etc.
