Why do Medieval English humans dislike merfolks, elves

<section id="nice" style="font-size: 16px; padding-right: 10px; padding-left: 10px; word-break: break-word; overflow-wrap: break-word; line-height: 1.25; font-family: Optima-Regular, Optima, PingFangTC-Light, PingFangSC-light, PingFangTC-light; letter-spacing: 2px; background-image: linear-gradient(90deg, rgba(50, 0, 0, 0.05) 3%, rgba(0, 0, 0, 0) 3%), linear-gradient(360deg, rgba(50, 0, 0, 0.05) 3%, rgba(0, 0, 0, 0) 3%); background-size: 20px 20px; background-position: center center;"><h2 style="font-weight: bold; font-size: 22px; margin-top: 20px; margin-right: 10px; margin-bottom: 0px;"><span style="font-size: 18px; display: inline-block; padding-left: 10px; border-left: 5px solid rgb(145, 109, 213);">Why do Medieval English humans dislike merfolks, elves, wizards and fairies in Medieval England</span></h2> <p style="padding-top: 8px; padding-bottom: 8px; line-height: 26px; font-size: 14px; word-spacing: 2px;">Because they were annoying, or, in some cases, downright dangerous. Merfolk would drown sailors and unsupervised children near the water, elves would kidnapped unattended children on the land, wizards were responsible for plagued and famine (or sometimes good things or just bad luck) and fairies would prank farmers trying to make their living.</p> <blockquote style="border-top: none; border-right: none; border-bottom: none; border-image: initial; font-size: 0.9em; overflow: auto; border-left-width: 3px; color: rgb(106, 115, 125); padding-top: 10px; padding-bottom: 10px; padding-left: 20px; margin-bottom: 20px; margin-top: 20px; border-left-color: rgb(216, 156, 246); background: rgb(244, 238, 255);"> <p style="padding-top: 8px; padding-bottom: 8px; font-size: 14px; word-spacing: 2px; margin-top: 0px; margin-bottom: 0px; color: black; line-height: 26px;">All of the above are metaphorical understandings of unexplainable real world events: a child drowns and the body is never found? Merfolk. A half chewed corpse of a sailor washes up? Sharks, merfolk or shark riding merfolk. A child got goes missing and is never found again? Elves. Your tools go missing in the night? Fairies.</p> </blockquote> <p style="padding-top: 8px; padding-bottom: 8px; line-height: 26px; font-size: 14px; word-spacing: 2px;">I am by no means an expert on this topic, so take what I have written with a grain of salt. This is just information I have collected from online browsing, books on mythology (Irish Fairytales by Jake Jackson was an awesome read) and general book reading, such as the Rangers Apprentice Series and the awesome book Three Hearts and Three Lions by Paul Anderson.</p></section>