I do agree with you in regards to that. I have always wonder'd myself.
The only thing I can offer you is my personal expierence with my mom.
I can tell you she has absolutely no desire to remain on earth. She can't wait to go to heven. As to how does she know she is going to heven. I don't know except that its something she feels very deeply in her heart to be true. And by the way, I can tell you that my mom has never said that she is going to heven and I do believe she feels that no one KNOWS absolutely for sure. She has always prefered to use the term "Hevenly Hope" So in her mind, and I'm taking a lot of liberty here, she believs that all who partake of the emblems do so because they have HOPE of going to heven. If others who say they are annointed disagree with that ..whatever.
Hope this answers your question a little.
plm