Have you thought of the Corruption chasms as nests, dug by the eater of worlds to harbor the shadow orbs which are its/her eggs? That would explain its anger after breaking three. I hope I did not miss anything from your worldbuilding.
I never really did cover the Corruption in-depth, so you didn't miss much of anything.And before I get started, remember, this isn't a theory as to what the devs may have intended, and this shouldn't have any bearing on how other people may decided to worldbuild the Corruption. This is only how I've decided to characterize it for my own stuff.The crux of my interpretation is that I don't consider the Corruption creatures to be biological entities, seeing as they're made of rotten flesh. They seem more like animated conglomerates pulled from a set of very similar templates, with a singular goal of spreading, killing, absorbing dead biomass, and spreading more.
That said, the chasms ARE dug by the Eater of Worlds, but also all the other burrowing Corruption creatures, of which there are many. They're just not a nest; they don't need to breed since they're not actually living things. It's more for living space and surface area for spreading the corruption, especially in its weakened state.
The Shadow Orbs themselves aren't eggs, they're actually more like pearls, where random objects that have fallen into the chasms get coated in layers of demonite or a demonite-like material. This mainly explains why you can find some fairly mundane items inside of them, some older ones being sufficiently suffused with Corruption energy to have changed their nature (whilst more 'modern' objects, like the Musket, remain unchanged, simply from not having been there very long). Smaller and heftier 'pearls' from minute particles are much denser can simply be taken, hence the light item.
They still act as acute focuses, drawing in the soul energy upon which the Corruption denizens feed. It explains why you hear screams when you break them, and why destroying or stealing them enrages the Eater of Worlds, which tends them and carefully shapes them into the familiar orbs. Who really knows why. Probably something to do with optimizing distribution or the material matrix for keeping the energy stored until needed.












