Is there any evidence that the Prophet (peace be upon him) did not always combine prayers while traveling?

Combining prayers for a traveler is a concession according to the majority of scholars. However, they differed on whether it is better to combine or to refrain from combining. The majority of jurists believe that refraining from combining is better, except in Arafat and Muzdalifah. As for the Hanafis, they do not permit it at all. The Malikis permit it when one is traveling intensely and fears missing something important. The preponderant opinion is that combining was due to necessity, as stated in the hadith of Ibn Umar reported by Abu Dawud: "The Messenger of Allah, peace and blessings be upon him, never combined Maghrib and Isha prayers during travel except once."