Rehearsal Dinner- Everyone for themselves?

To be quite honest I'm having a hard time grasping around what rehearsal dinner is supposed to be (besides dinner after the general rehearsal for the wedding). We're already having to spend a ton of money on the wedding itself and, should we decide to have rehearsal dinner, it's the tradition to have it paid? Has anyone had an experience where you just all go to a restaurant and everyone pays for themselves? I really don't want more pressure on myself for dropping more money on another venue