Yes i usually plan with snipers in mind. But then i also snipe myself. Not as much to be too fast for others to react but so that i have no time to decide on raising my bid. When you get in to a bidding fight with someone as the last minutes tick down you will not think about if the price is still reasonable and keep offering more and more, in the end paying twice as much as you originally meant to spend.
That way i decide what a sensible price is beforehand and just stick with that. If i win it yay, if not then ah well wait for another one to show up. Because ebay bidding makes you win an item for slightly over what the 2nd highest bidder gave means that there is less benefit to sniping. Its not the typical bidding method that you see at real auctions. This is more like everyone submitting there entries of whats the highest they want to pay for it, so if you offer more than everyone else then you win. The current winning bid price is only there as a guide to let you see what sort of price range its going at so that you don't bid on something that's already going for a few grand and expecting to win it with your100 dollar bid. This system makes bidding just slightly higher than the higher bidder a bad strategy. Just bid the highest you are prepared to pay and leave it.
Yes ebay auctions can sometimes be incredible bargains if you are lucky, but a lot of times a item you want attracts the attention of too many other buyers with deeper pockets than you that fight the price up.