Absolutely. The Frumentarii were local agents who supervised the collection of grain in a specific region or sometimes all the way up to the Provincial level. While he didn't concept a national intelligence service, Hadrian realized the idea that Rome truly needed a national presence and he schemed to engage the Frumentarii since they were already very well established in local contact with farmers, merchants, and the local lay of the land. He used them to report back on his friends, on his enemies, and in concern with military operations to gather local intelligence for specific use.

One of the most critical elements in military operations before the advent of more modern technologies was 1) knowing the local geography and 2) exploiting it to your advantage. Rome came to rely on the Frumentarii in this way frequently during the 2nd and 3rd centuries in addition to other concepts we associate with spies, like keeping track of local and regional political intrigue.

I would recommend you give The Making of the Roman Army from Republic to Empire from Lawrence Keppie for more information on the subject.