Well, I personally always have the walkway up to my house shovelled and salted before my first clients show up if there has been snow. My husband usually does it before he goes to work, but I have gone out and done it sometimes before pick up quickly. It literally takes me 5 mins and I do it while the kids are in their booster seats.
Last winter, I had one of my dcmom's slip and fall while putting her daughter in the car. However, she was wearing 4 inch heels...and my driveway was shovelled and salted. Totally her fault, but she did tell me.
I look at that this is my business and it needs to be done for the safety of my clients. We would expect it of any other business. That's just my own thoughts though.