Calculators with a "typewriter-like (qwerty)" keyboard are forbidden, but they allow the TI Nspire CX, which has an alphabetic keyboard (albeit in the order abc

Calculators with a "typewriter-like (qwerty)" keyboard are forbidden, but they allow the TI Nspire CX, which has an alphabetic keyboard (albeit in the order abcde). What kind of stupid rule is that? (Especially considering they don't clear memory, and one can install a full Debian distribution on the Nspire CX...)