Well ... I hate to advertise our technical debt but we've got a couple of mainframes that store every character string in upper case because no one has bothered to convert from the original EBCDIC [1] ... THIS IS REALLY GOING TO BOTHER ME!
"BCD ("Binary-Coded Decimal"), also called alphanumeric BCD, alphameric BCD, BCD Interchange Code, or BCDIC, is a family of representations of numerals, uppercase Latin letters, and some special and control characters as six-bit character codes.
[...]
IBM later created the 8-bit code EBCDIC (Extended Binary-coded Decimal Interchange Code) based on BCD."