وابن السبيل: من كان له مال في وطنه وهو في مكان لا شيء له فيه
Translation: Ibn al-sabīl owns wealth at home but has no resources where he is staying.
A traveller may have assets in their home country yet lack access to funds at the present location. The relevant issue is immediate inability to use those resources.
For example, someone who loses access to money during an otherwise lawful journey illustrates the situation.