Isn't it the same with alcohol? Ever tried non-alcoholic beer (I haven't, but I don't drink the real deal either)? Why would you want to replace beer by non-alcoholic beer? You only fool yourself, don't you? If you want it to taste like beer: have the real stuff. If you want to quit drinking beer, drink something that doesn't even come close to the taste. Otherwise you keep tempting yourself, I would think.
Now how about fake cigarettes? The commercials on TV make us believe that there is no problem switching to fake cigarettes if you want to quit smoking. You can even smoke these cigarettes in the house, because they don't smell like cigs. The (grand)children will no longer hate you or wave the polluted air out of their face if you smoke in front of them. Does that make smoking more acceptable? Or is it another form of disillusion?
Would there be a substitute for insulin? If there would be one, I wouldn't want it to be fluid. I would want it to be crunchy, carb-free, tasty and well seasoned..