That's right, but factories have other problems too: especially EMI due to huge loads being switched, which twisted pairs, shielded twisted pair and ethernet te

That's right, but factories have other problems too: especially EMI due to huge loads being switched, which twisted pairs, shielded twisted pair and ethernet termination magnetics are designed to resist. Also, industrial cable routing can get pretty hairy, this means the ability to round a corner at a relatively tight radius can be important. Using standard ethernet cables for low current DC power keeps these concerns generally within acceptable realms of normality.