I certainly understand the issue. It depends a lot on where you hail from too. For years seeing snaggers with sponge or fake eggs as decoys for the wardens turned my stomach. Then seeing a stream packed with anglers and snaggers all with a glowing ball on their lines associated egg flies with that zoo mentality. But..I got over it. For really good reasons.
Eggs are a hatch matcher all winter long, and not just on the Great Lakes tribs and Alaska. Trout dump millions of eggs every fall and spring in every stream in the country. Then, spates roll them up into the drift and they settle in quiet areas to be gleaned. Eggs are trout food. I have found them in trout stomachs all winter, but esp in late fall and mid spring -depending on trout species. The sucker spawn SlateDrake mentions is a later spring deal but every trout stream has them.
Brown eggs are yellow-ish to pale orange-ish, brookies orange-ish, and ‘bows pink-orange-ish, suckers pale yellow-ish or yellow-greenish. But…you can use enhanced colors effectively –chartreuse works really well for browns. Bows seem to like pinks.
For stream trout I've gone to those tiny “pom-poms” you can buy in craft stores for next to nothing. I use the yellow and pink ones. With a sewing needle I introduce matching color tying thread in the pom-poms center and then lash this to the hook shank. Some supporting wraps under the egg will keep it on top of the shank so it doesn’t roll down into the gap and cause hooking problems. Do not use those super short shank “egg hooks” , esp up-eye ones –they can cause consistent hooking problems. Lotsa hooks work.
I use Glo-Bug yarn too –for bigger egg flies –like for steelhead, etc... If you use it, tie them small for stream trout and trim the yarn below to keep the gap open.
You can invent your own as well –any bright hued material –marabou, yarns, dubbing, etc… Doesn’t matter; trout will recognize them.The brighter the better often, esp if there's any color to the water.
A pom-pom egg fly that duped a small stream brown over a 1000miles from the nearest Great Lake: