What’s the point of the HSBC Gates?

These steel sculptures between St Paul’s and the formerly wobbly Millennium Bridge seem rather pointless. Corporate branding of what are effectively lumps of metal, whatever next? They don’t even restrict access to the area for vehicles, there are bollards for that.
Apparently HSBC donated some money towards the construction of the bridge.
Top Photo: The HSBC Gates^ by Chris Guy (CC BY-NC-ND 2.0)