Totally agree, spoke to another wc the other day and he told me a mate of his cleaned a few years back, custy slipped on ice due to water freezing on floor and he was taken to court and lost had to pay custy £15,000 plus costs, insurance wouldnt pay out as it was down to stupidity of working in minus conditions and putting salt down proved more so as he new of the dangers 
Probably just hearsay :
I'd like more proof as to if it was true though.
The person who it happened too is a local guy, why would it be hear say, trust me it wouldnt be difficult to cause a slip hazard and custy to fall on it, especially those who pole shop fronts and around the front door 
its very likely going to happen more and more, my dealings with "no-win , no-fee solicitors" have been a real eye opener
lets face it, its just dangerous to do, we all know the water will freeze, water will take ages to dry in this weather and when the sun goes down and the temps drop, it'll just turn to ice