We can't read the manufacturer's mind, but usually labels are only destroyed off of main chips to keep manufacturing secrets. Removing the label from a capacitor is useless because the capacity can be measured without difficulty if the product is working and people are just trying to reverse engineer it.
Likely there is no label because the part is too small or difficult to label, like a ceramic capacitor, or it's just really cheap and labelling just adds to the production cost.
Like mentioned, if it's in a specific part of a circuit, like decoupling a chip, or filtering right before/after an LDO it's not hard to make an educated guess.