digital*ghost, UPC numbers will not be mandatory as stated by their policy http://sellercentre.ebay.com.au/news/sp16/structured-data headed,
2. WE’LL ACCEPT NON-STANDARD PRODUCT IDENTIFIERS ON EBAY.

Looks like eBay will be so keen to retain business they will create their own identifiers for sellers to use. If they go down the UPC barcode track of charging, then my guess is a lot of sellers will create their own under:
Private label product identifiers (seller- generated identifiers)
It's going to end up being largely irrelevant and a complete waste of time for both the seller and the consumer. For goodness sake, I don't even remember my car rego number when I book it in for services. Products change so quickly these days, new models come out, updated firmware happens in days, cheaper to buy new rather than repair, a number to identify something supersceded within months will be a totally irrelevant concept. In fact, it could end up causing people to buy old, outdated rubbish and not keep pace with innovative trends or new, highly efficient, local, social-networked or cutting edge product that does not see any need for bloated UPC like numbering technology.

Regardless, the situation at present is hopeless for sellers who get stuck in a UPC field loop and can not edit listings. It's plainly very bad when the help people can not fix the problem.