@alvianosi : he is hiring himself out as a porter using his storage a ability, because it is his only marketable skill, right now. From other series I gave read, unless such storage is common as hell it could easily draw the attention of people he needs to avoid. If it is rare then any smuggler, merchant, nobles and even the king who summoned him would all have reasons for wanting to control him and his life.
Heck they could want him as a "servant" for whatever noble/prince/princess/etc they have tag along with the hero party to control them, so they could live in luxury while on the mission.
That and kicking out someone who you summoned is a huge corrupt king(dom) red flag.