Painted Egg

Count in tens. The painted egg's text mentions no surprise inside, only a trade: ten of them become one bronze egg. That trade is the whole reason to pick them up.

So the hunt turns into a numbers race. You run the field with an egg basket and grab every egg before the guy next to you does, because a remainder that never makes a full ten is worth nothing. The stack holds a thousand, so the pile never needs a second slot. A Bunny Onesie or the ears help you spot more of them, if their descriptions are right.

When the hunt is over, upgrade every full ten straight away. For the odd few left over, neither the row nor the game text shows any other use. And it has nothing to do with the chicken egg from the Food tab, which you eat or hatch in a coop.