The only answer I can think of for your question is that
Languages have many differences. If all verbs matched up perfectly, in meaning and usage, such as transitive/intransitive, reflexive/not reflexive, then we would lose the beautiful variability and richness of the world's languages. How boring that would be!
However, I thought you might like to know that there's another way of expressing the same concept, that is reflexive (pronominal):
darse inicio
Las clases se dan inicio el 27 de agosto.