Oil companies must be feeling the burn from declining gas prices. I don't know much about the oil companies, but can imagine they are not very happy right now. Things always rise and dip, so it is just their turn to be in the red and consumers of gas get to benefit.
Anyone with even a rudimentary understanding of the principles of economics understands this basic concept: supply and demand. In this case, the lowering of the price of gas to a figure lower than that demanded by the market means that consumption will accordingly increase, thereby straining production facilities and eating into long-term supplies and perhaps profit margins.
Oil companies are not at risk as a result of the declining oil prices. Oil companies have systems in place to ensure financial viability during times when oil prices drop. These companies understand that oil prices are dynamic, not static, and these fluctuations are a natural part of the business.
Oil prices have always fluctuated, and oil companies business models have been built around this. Additionally, with gas prices lowering, it could be assumed that there will be less push to purchase hybrid or electric vehicles, which could increase market share for gasoline producers. The lower prices also keep people from worrying about how much they're driving.