3 Parameters in pg_settings in CamelCase

Hello %

Is there any particular reason why 3 parameters out of 326 (in PostgreSQL 12.4) are in CamelCase?
At least when you query from pg_settings.

(postgres(at)[local]:55000)[postgres]> select name from pg_settings order by name;
name
----------------------------------------
...
...
DateStyle
IntervalStyle
TimeZone
...
...

All others are in lowercase. Even in the postgresql.conf these parameters are in lowercase.

$ cat postgresql.conf | egrep -i '(datestyle|intervalstyle|timezone)'
datestyle = 'iso, mdy'
#intervalstyle = 'postgres'
timezone = 'Europe/Zurich'

Cheers
William

________________________________

Disclaimer:

Diese Nachricht und ihr eventuell angeh?ngte Dateien sind nur f?r den Adressaten bestimmt. Sie kann vertrauliche oder gesetzlich gesch?tzte Daten oder Informationen beinhalten. Falls Sie diese Nachricht irrt?mlich erreicht hat, bitten wir Sie h?flich, diese unter Ausschluss jeglicher Reproduktion zu l?schen und die absendende Person zu benachrichtigen. Danke f?r Ihre Hilfe.

This message and any attached files are for the sole use of the recipient named above. It may contain confidential or legally protected data or information. If you have received this message in error, please delete it without making any copies whatsoever and notify the sender. Thank you for your assistance.