2013~2016 Rear Wiper question

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Mazda3 GT
I took home a 2016 Mazda CX-5 the other week and the Rear Wiper has been bugging me. The top option is Fluid-only while the bottom is Fluid + Wiper. Shouldn't both should be Fluid + Wiper? I can't see a reason to use the Fluid-only.. The one I need most of the time is the one on the bottom which takes more clicks to activate. So my question is, is this normal or mine is broken?

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