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Hate to ruin your meme guys, but from a game design perspective, this makes sense. This is a way for new players not familiar with the many, many, monsters to determine the typing of a particular one. This allows them to make the call to catch it or not, or to choose an appropriate super-effective move, etc, without looking it up, or needing a guide.
There are exceptions to this rule, like Solrock, but I bet a lot of you thought Solrock was part fire the first time you saw it.
Other mons such as Vulpix and Heatran, rely solely on their coloring to tip the player off. If Vulpix were white or grey or brown, it could pass as a normal type. Heatran, if the red elements of it were changed to green, it could pass for some sort of grass type. All because neither have some overtly "fire-type" aspect to their design, like Charizard or Magmar.
tl;dr it's so new players can know types, and experienced players can remember them.