It all about fertility, baby. And that's about sex and well, babies. Making out like bunnies, making baby bunnies, eating baby bunnies, smelling the pretty flowers, enjoying sweet drinks, boozing and carousing and dancing around in the freshly plowed fields.
Christians took this perfectly wonderful celebration of nature and decided to slap a lot of suffering, torture and death onto it. Like there was not enough of that the rest of the year? Oh, kids, sorry, no more orgies, but you get to color eggs, hide them, find them and eat them. And wear a nice outfit to the suffering, torture and death meeting.
Leave it to the fundies to suck all the fun out of everything.