Not random at all, I wondered exactly the same thing before I bought them. I've used Etymotic HF5 and ER20s before and hated the feel of the silicon Christmas trees they use. It was a bit of a leap of faith buying the ER4XRs and the earmolds at the same time. I knew I'd never love the foam...
My ear molds were made by Australian ACS dealer Pacific Ears. Looking at the way they made my patterns and the final product it appears my ear drums are only one or two mm from the tip of the ear mold.
The foam in the image was pressed against my eardrum before the mold was made. They were...