"Who really starts items at low prices."

Probably they are likely to be new sellers who hope that their item will find "its own price level", or those who have no idea of an item's value and hope for the same thing.

Very likely they might have read ebay's Help Page where it still says :

"A low starting price helps attract bidders"   Despite (as you note) this hasn't been true for years.  

In fact, with private buyers being far thinner on the ground these days, all the unwitting seller is likely to attract are a few re-sellers who will only bid the start price to maximise their profit.  Which is why so many auctions end with only one bid. 

It's just one way that ebay abuses the trust of (usually) private sellers by allowing them to be used as a cheap re-stocking resource for businesses if they are daft enough to follow ebays advice and just one of the reasons that private sellers/buyers are looking elsewhere to sell their unwanted stuff.

Who can blame them for refusing to sell granny's diamond tiara for 99p when they've been so blatantly mis-informed and given such bad advice by the auctioneer?

Ebay SHOULD be giving sound advice to its customer (the seller) and advising them to 

a)   Set the start price at the lowest price they find acceptable.

b)   Do their own research before even thinking about selling the item.

NOT offering them up as easy pickings to a flock of vultures.