Washing Windows ... I think?

We went into Sydney today. I didn't WALK in, you understand. We took the train. Pre Christmas in the middle of downtown Sydney's shopping precinct is a "blip-rich environment" to say the least. From a packed field of contenders I thought that this image might prove interesting. Here are two blokes who appear to be doing a job that I have always wanted to do ..... NOT!! It does seem to be an odd setup for window washing but I can't think what else they'd be doing. Can anyone guess?