He came along for fun or pleasure rather than a serious purpose. Eg "I'm just coming along for the ride, I have no intention of joining the team".

I have to disagree, not in principle but in effect. . to "come along for the ride" is usually figurative of not participating fully; possibly not doing the work. . All the people who came on this workgroup are supposed to also teach on Saturdays at the local rural school, but EBAN seesm to go sightseeing on Saturdays. He really only came along for the ride. . Can be used when no travel is inolved. This class is mostly people studying for pre-med, but some of them are just students who seem to have no intention of doing anything serious, they really just came along for the ride, perhaps escaping having to get a job.

"My friends wanted to go to a rap concert. I don't like rap music, but I decided to go along for the ride, so I went with them to the concert."