I have placed a start bid on ebay to keep a seller from pulling an item off early. (The seller had prematurely ended the same listing due to no bids before, not knowing that I had a snipe bid ready, of course.)
I've also bid on ebay just to thwart a Buy It Now option. In fact, I did that just last night.
In both cases, my first bid seemed to send a message to other bidders, "Come! Bid Here!" Both auctions got bids soon after mine and ended up with lots of bids. (This after days and days without bids before I jumped in!)
I ended up losing the first item, but winning the second.
I guess I'll just snipe as usual and take my chance on an item being pulled unless it is REALLY, REALLY, REALLY important to me. If no one bids, I can always contact the seller and ask if he/she will relist the item at an acceptable BIN price, and let me know right away so I can snag it. I've done that several times with good success.
I have often seen people bid items up way over what the original BIN would have been. In fact, I tried to snipe an auction in which a bidder bid low to remove the BIN price, and then struck back against counter-bids every time, until she finally won the item at considerably over the price she had been unwilling to pay in the beginning.
I may still sometimes place a low-ball bid on items with great big BIN prices. The one I won today was still $100 under the BIN, so I'm glad I played it that way.
Anyway, hard to say.