EDIT: OK, let me help you arrive at the destination: your machine gets dusty and slow, just as if its electronics was failing. You take it to Apple and they fix it under warranty or ask for some $$ if it's out of warranty (given that they have to spend time doing it, time that you would be spending yourself, whether it's easy or hard to open up the machine). Calling it cleaning or repairing is splitting hairs. If it's degrading performance, it's a problem, if it's not, it's cosmetics.
BTW, all this fuss with cleaning fans — no one I know opens up their stuff and clean the fans until the device malfunctions. You are in the small small minority and no company, including Apple optimized for your habits.