That's just it. A lot of people seem to think of multi-tools as tool replacements, and they just aren't. If you're doing real work, you're still going to want real tools. Where a multi-tool shines is simply the packaging. They're compact enough that you can keep them places where you can't easily keep the equivalent set of full size tools. This makes them great for those times when you just don't have access to real tools, or when you just need to do some small task that doesn't warrant opening up the toolbox.
x2. It's like Paul810 is reading my mind. Even though I love them, they are not a substitute for real tools. I will rarely use a multi-tool at home for when I have access to regular tools, except for something very minor where it's not worth the trip to the garage. If I expect I'll need tools for something outside the house, I usually bring a small toolbag instead. Where the multitool really finds a niche is for unexpected repairs, which happen often enough that the multitool is perfect, but it's not something I rely on as my primary tool.
If you're cranking on a multi-tool to the point where you really feel you are going to break it, it's probably time to go find some real tools.
Of course, the exception to that is if it's some sort of emergency where you need to do something right then and now, at which point you probably won't care if you twist the h*ll out of your multi-tool, as long as it gets the job done. Those are the instances where your worry of breaking your expensive multi-tool gets outweighed by the relief you got from having that multi-tool available to you when no other tools were around.
True, some people seem almost proud when they break a multi-tool, like it's a badge of honor. In an emergency it's understandable, but if you're breaking them often it's a sign that maybe the multi-tool isn't the right tool for the job. Similarly, I've never been a fan of the jumbo size nearly 1 lb. multi-tools with all the add on accessory bits that require a huge belt pouch. By the time you're carrying that much weight and bulk, you're almost better off just carrying a few regular tools which will make any type of repair work a whole lot faster and easier, with less chance of damage. I think with all the competition to have the most features, companies have strayed from the original design intent.