Exactly. Swap kills the card. But even if you turn the swap off (in linux or windows) I think these systems still write more often than amiga-like systems.
BTW: Do I have to 'shut down' MorphOS before I turn the computer off or just push the power button like I do in Aros?
Yep. Writes kill these cards, and most mainstream OSs do a lot of writing, even without swap. They write icon and window sizes and positions, last used item lists, log files of all sorts, last accessed metadata and so on. I'm not familiar with MorphOS at that level, but AmigaOS was never much into writing to the disc unless you wanted it to - you could even boot from a read-only partition if you wanted to. I guess MorphOS follows that to a certain extent too.