Actually, the 5K orders are market maker (MM) orders that are the standard amount for this level of price with the stock. The higher the stock moves in price, the fewer the number of shares are at each level. For example, if the stock passed the one dollar mark, I think the number of shares that the market maker will offer on the bid and ask is blocks of 100 shares.
The difference is when a trader/investor shows up and places an order. If it's not an AON order (which can be hidden), it'll likely show up on LVL2 on the bid or ask, depending if they're buying or selling.
The standard MM orders are basic, and required to keep the stock liquid, but it's the traders/investors, and even those selling that create the market.
It's also true that the MMs can move shares to manipulate a stock. They can move shares between each other to get a stock moving, and they can also naked short a stock to make up for losses uncured on major runs. They make $$$ on volatility, so they actually manipulate it both ways.
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