It's likely just newbies getting too caught up in bidding wars for stuff they have no real knowledge about.
When I first got on eBay in about 2002 I was so excited at the prospect of buying Vintage again (I hadn't bought anything for like 10 years) that I immediately got caught up bidding on things that were ending in the last hour or so (In fact for a little while I felt that was the best way to search for things, especially late night - hoping that I would get a bargain!)
I remember the amazing feeling I had when I won my first auction too..a rare Kenner boxed ROTJ INT-4 with one flap torn off, writing on the box and the cannon thing on the front glued on.
I won that INT-4 for a whopping £45 I think and that was 13 years ago now so there have always been twats spending more than they should on Vintage. :lol:
It's a learning curve
New movie hysteria combined with "newbies" generally creates a pretty ludicrous market but these people come and go. You either get smart quick after making those kinds of mistakes and start doing your homework, lose all your money because you've no time for homework or you just give up after the first few impulse buys.