Understanding the practical reason behind the request.
Rental staff aren't trained to verify the authenticity or details of driver's licenses from every country in the world, so an internationally recognized translation format gives them a consistent, quickly verifiable document alongside your home license. This is especially relevant when your license isn't printed in the local language or alphabet.
Even where not strictly mandatory, presenting an IDP alongside your license tends to speed up the rental counter process and reduce the chance of a hold-up.