Bikinis used to cover more until now. They were design to be suitable for swimming as in not weighing you down, undergarments are not. There are one-piece swimwear. Female undergarment was invented to cover your "womanhood" since originally girls used to wear mostly skirts.
The two bottom images actually mean "I would like to object, but this is so weird/dumb/fucked up I don't even know what to say".
I think that's not the kind of reaction images you should put here.
I think that's not the kind of reaction images you should put here.