My different take on this:

Your inability to accept the candy is intentional on the part of your mind which put that event in your dream. It is offering the candy and simultaneously blocking your ability to accept it. This is demonstrating the control it has over your will and your awareness, and also suggesting that you are blocking your ability to accept what the candy represents by the control that you're trying to exert. The course of action that everyone else is advocating is to work to overpower that part of your mind. I agree that such an effort will almost certainly result in a higher degree of dream control. But you'll be giving up the candy, and it may not be offered again for a long time. This isn't a matter of obstinacy on the part of the offerer, its a matter of the trajectory you take. My suggestion is to enter into a dialogue with the candy offerer, listen to it, meet it part way, dance with it, not pushing it out of the picture by taking full control of the dream. Don't worry about accepting or not accepting the candy, and don't worry if that image is never presented again, its the dialogue that matters.

What I'm suggesting is more like the route I took. For me there remains the issue of integrating myself with the candy offerer, if that's even desirable. This is a problem I'm still working on. But my way led to other remarkable experiences that most overt dream controllers appear to have trouble reproducing. Maybe you can try something that's not quite what I did, but also not what the other people are suggesting, and that will lead you to somewhere else uniquely interesting. Perhaps, for instance, you could work towards being more fully lucid while consciously and intentionally leaving space for the 'other', from the outset of your development, rather than aiming for the lucidity first then reaching out to the 'other' later. That would be different from what I did, in that I pretty much blew off the dream control part entirely, while focusing on the lucidity of other aspects of my dream-time and waking-time thinking.

Although your dream may be accurately characterized as only very weakly lucid, I consider it to be valuable. Its small, but its a door, and I wouldn't trade it for an hour of fully lucid battling with flying orcs.