What's the connection between the word 'roam' and the cell phone roaming? [closed]

The mobile subscriber is unaware when they move from one telephone operator's region to another, so from the perspective of the telephone operators, they are indeed roaming aimlessly from region to region.

And the etymology for roam suits that well

possibly from Old English ramian "act of wandering about," which is probably related to aræman "arise, lift up."

The food/employment mentioned by OP is just an example used by one particular dictionary's roam definition.

EDIT : originally I answered describing subscribers moving from cell to cell which in GSM parlance is actually called handover if it's during a call rather than roaming.

As commented by FumbleFingers, roam is a synonym of travel.

The definition in Learner's Dictionary should also help:

to go to different places without having a particular purpose or plan

From the communication service provider's perspective, the notion of the subscriber wandering in geographical regions where their service is not directly available ("different places") must imply "roaming".

Further, as per a Wikipedia article:

The term "roaming" is actually ancient and does not originate from any technology at all. Roaming barbarians have been mentioned by Egypt and Roman historians already, roaming simply means the process of moving around the countryside without regard for who the lords of the individual strips of land are that are being passed through