How to say “Why is the creamy conditioner always twice the price of the runny one that does nothing for my hair?” in Japanese

In Japanese

なんでクリーミーなコンディショナーって、いつも水(みず)っぽいほうの倍(ばい)もするの？あっちは髪(かみ)に何(なん)の効果(こうか)もないのに。

Nande kurīmī na kondishonā tte, itsumo mizuppoi hō no bai mo suru no? Atchi wa kami ni nan no kōka mo nai noni.