Just because stimulants _can_ get you high and be addictive doesn't mean they will when taken appropriately. The only time I felt any kind of high from my ADHD medicine was the first day I took it. And I quite easily skip taking it on weekends, with the only side effect being that I browse the internet all day and struggle to do anything productive.
To be honest, I don't actually like being on stimulants. Methylphenidate made me feel like I was constantly in low-grade fight-or-flight mode and dextroamphetamine (which I'm on now) gives me mild emotional blunting. Plus both cause slight dry mouth, appetite suppression that I have to forcibly eat through, and insomnia if I take them too late in the day. Not to mention the fundamental hassle of taking pills every day within narrow bands of time, something I regularly procrastinate and/or forget. (Also, I have tried taking higher/double doses as you suggested earlier when I was figuring out my optimal dose. They just made me feel jittery and on edge - not exactly pleasant.)
If I had no ambitions or responsibilities, I would be more than happy to throw my medicine away and sit around on my computer all day every day. Unfortunately, I do have ambitions and responsibilities and medication helps mitigate my crippling, career-threatening inability to get things done. So I'll take that tradeoff.