I have a lot of customers that get this condition a lot right out of winter. This can be a serious problem but also may be minor.
If you noticed once all the snow is gone and the lawn is beginning to green up except for maybe a few inches along the sidewalks and driveway, you may have some salt damage.

Typically I find that when people apply sidewalk salt or ice melter over the winter, a lot of people feel the more the better. This is not the case. Most brands of salt or ice melter have specific instruction on the bag on how to apply and how much to apply to the surface. I strongly recommend following these instructions.

When the instructions are not followed, there will be some runoff when the product melts the ice. there will be some shoveling done and place onto the lawn etc. This will initially cause the lawn to suffer and may even lead to the lawn dieing off.

I know what your thinking. Man was I getting tired of falling on my but all winter so I really didn't have a choice but to poor the whole bag on the sidewalk.
Well that is understandable because if you are trying to sit there and watch the ice melt, it is as bad as watching paint dry so you tend to go overboard until you hear the crackling and popping as if you are having a bowl of Rice Krispies.

Well just remember next winter, just because you do not instantly see it working, don't  think that it's not and don't apply more. Follow the recommendations and wait. Not only does each product have application rates, but they also let you know what temperatures to use the product in.
If you are attempting to use a product designed for 5 to 35 degrees, but the temperature is 0 degrees outside, adding more product will not help. Getting a different product or waiting until the temperature rises to apply it will help.

Well it's to late and I applied to much: If more than two weeks has gone by and the rest of your lawn has come out of dormancy and these areas have not recovered yet. seeding the areas will be your best option. View How to section for seeding instructions.

I don't want to wait for the seed to grow: Sodding the area is a pretty quick fix and if your are only doing small areas, it is relatively inexpensive. View How To section for sodding instructions.

What if I had a company salt for me: Well I am no lawyer, but if I were salting your sidewalks over the winter I would probably over due it on purpose. The last thing i would want to happen is someone to fall after I salted. Not only would I feel pretty bad, but I am sure you would try to sue me. If this company also does your lawn, they are probably use to this request and will probably fix is for you.