Do most bitcoin users actually think that bitcoin is going to 'replace other currency, ATMs on every street corner', etc. at some point in the future? Is such a future actually necessary for bitcoin's continued success or maintainance?
No, and no. Arguably Bitcoin is already a great success for the people it appeals to, and it could very well always remain a niche, or subculture. There is no need for it to replace anything to be successful. It can just add to the world. It's not a zero sum game...
Your question is a bit like asking "Will Linux ever replace every computer operating system in the world"? Sure, with web servers (and later Android) it made a great paces toward large share of the computational devices on the world, but it hasn't replaced anything.