Because of the prestige, power (and connections) it gives. All of these can be monetised later when high-profile jobs run out.Quote from Debaser82:
He only made 300K$ a year!
Why do people accept such high stress and profile job for such low pay?
For example, Tony Blair earned in the range of £150k per year as British Prime Minister. Now he charges up to £250k for a 90-minute speech and is believed to have earned over £20mln in the 3 years following his resignation.