Cryonics is a field where raising awareness is genuinely beneficial to the believers- not just to the administrators of related organizations. Being frozen and then revived requires (inter alia): a dedication to proper freezing maintenance, a method of revivification, a willingness to spend resources to revive you in particular, and experience in curing/reviving humans. If cryonics falls out of favor for any period of time, the dedication to proper freezing maintenance is likely to suffer. The more people that are frozen, the more avidly entrepreneurs will seek to invent methods of revivification, and the more experience physicians will have in treating the newly-revived. If you do not have a plan in place to ensure that you will actually be revived once it becomes possible, you may at least hope that people you've convinced to be frozen may remember you.