My company blocks MSN messaging or any instant messaging at work

I feel my company in the financial sector is pretty outdated and has been
blocking MSN messenger or Yahoo or Google Talk at work and not only do they
block IM tools but also personal email sites like Hotmail,etc.

My question to you all is

Is it normal for companies in this financial sector to block all this at
work ? Or are we too paranoid ? I would like to get some examples of
companies in this sector such as banking/financial/insurance that have them
enabled so I can pass it on to my management and ask them to be a bit more
flexible.

Thanks