Many sites with sensitive information (such as banks, brokerages, etc) are coded to prevent saving login information. This is for your protection to prevent unauthorized access to your account.
This is unfortunate. There is such a thing as too much security, like how the guy was able to crash the German plan because the cockpit was too secure. and the apple fiasco. On one hand they want us to have "strong" passwords and to keep changing them so that it is not something that will be easily remembered and a pain to enter on a mobile phone. Then try to prevent auto login.
And it is not entirely for our security, partly for theirs to avoid liability and embarrassment
