Date formats are understood differently in different countries. When you format a date, it can be misunderstood if the date is presented as, for example, 06/03/2014. Some people read this as June 3, other people read it as March 6.
The solution for any database that may be used by people in different countries is to use the Custom feature to present the date as 06Mar2014 or 03Jun2014. But it is time consuming to have to do this again and again if you have various dates on various layouts. The date format cannot be preserved with condition formatting or styles.
It would not be a big engineering challenge to put one more date format into the option list of date formats. It doesn't change anything about the date entry. which can still be mm/dd/yy or whatever is set by the region/country preference of the user who puts the data into the database.
This is only a request to put one more format in the drop-down list. If it is found worthy, perhaps add a second one which is the ISO date format: YYYYMMDD