One of my pet hates too, together with its variants such as " Passengers are advised that...". These phrases are usually completely unnecessary. I suspect that they are written by people who are not thinking about clear communication. One of my favourites is in the toilets at Luton airport, which starts, 'Members of the public using these toilets are advised that...' It's completely redundant!'
I have great sympathy for visitors who don't have English as a first language who have to cope with these phrases. And all this was prompted by the Heathrow airport website instructions on travel between terminals: 'Please be advised that bus service 482 travels from...'