First, I want to discuss how this is simply not true, because nothing is free in the world and servers do have their limits. People fall for this misconception all the time, and the term unlimited bandwidth is tossed around all the time. I personally tend to stick with web hosting companies that will tell you their limit.
The words "free web hosting" do not appeal to me, because these free hosting sites come with a lot of drawbacks. For instance, you do not get any customer support, at best you will get a support ticket that takes several days in order to get a response from it. 99% of the time they do not even provide you with a phone number where you can reach them at.
Another problem I have with free web hosting is that they are loaded with advertisements. The service is "free" and that is how the hosting service makes their money. It makes no sense to me to run a website that is plagued with all kind of advertisements that draw readers away from your site.
Another common reason that people fall for free web hosting unlimited bandwidth is because they seem to think that web hosting cost an arm and a leg. However, these free services can shut your site down for any reason that they see fit. They do not have to give you a reason at all. In fact, one of the main reasons they tend to shut your account down is because you are hogging their bandwidth.