These other companies you mention are public. While their pension liabilities may not hit their "Net Income" all the time, or to the same effect, you can find their costs in the notes to financial statements. Also check out the "Comprehensive Income Statement". I once had a job where my job was to scan those notes to financial statements and report back which companies were manipulating their pensions the most. Have an unfunded gap? Just increase your estimated annual increase in the stock market and "poof" you suddenly have enough money and don't need to transfer more to your plan to keep it afloat.
As a CPA, I have long felt that Defined Benefit plans (You will get 70% of your pay from retirement until death, etc) should be illegal. The company is mortgaging its future and all of those pensions that people expect to have could be taken away through bad investment luck, fraud, etc. An example is the US auto industry, which has been crippled by their pension obligations. This wouldn't be a problem if employees were on a 401k plan or similar Defined Contribution plan.
To further the problem, imagine an executive faced with a labor strike. Answer: Promise them pension benefits. What does it matter? You won't be running the show in 15 years when the promise comes due, your company goes bankrupt and everyone loses their pension.
You see in this problem in the federal government as well. Social Security collection dollars have been larger than pay-outs since the beginning, but that will change. Where has the money gone? It is has been transferred to the Fed Gov general fund where it has been used to fund wars, roads, and promises elected officials make to stay in office. "The American Republic will endure until the day Congress discovers that it can bribe the public with the public's money."
