Tails can help you with anonymous navigation, but there are actions as user you can perform that would void that anonymity, easiest one is to log in to any kind of website that doesn't keep all the traffic in a secure channel using HTTPS, but there are many others.
On the other hand, public terminals usually have their setups locked, so maybe you can't select the USB as boot-up device.
All that being said, I think is good to know the option exist and keep it as another tool that you can use if needed.