The thing is, with emojis the differences introduced by font designers can be very subtle. In the GP's case, the laughing emoji seemed so much out of place and violated social protocol so heavily that I assume the confusion was probably cleared up later on.
But what about cases where a font designer changes, say, an emoji face with a light, content smile to a shy smile? This has the chance to undermine the entire emotional content of a message, without sender and recipient ever noticing.
For a more concrete example, have a look at https://emojipedia.org/beaming-face-with-smiling-eyes/ . Is it just me who thinks that the glyphs by Apple and WhatsApp show a beaming face with a somewhat sly touch whereas most others simply display happiness?