Unless you are using Dedicated Servers, a normal hosting package uses shared resources i.e. multiple users share hosting packages on the same server. As technology & the capabilities of our servers continue to grow, we can continually allow you to do more with your hosting package and its bandwidth. This means that we can offer practically unlimited resources for legitimate users of our hosting products who use them for the right purposes.
The way shared hosting is sold has undergone substantial changes over the years. In earlier times hosting companies and consumers would obsess over every single parameter, i.e., # of database accounts, # of FTP accounts, amount of bandwidth, amount of disk space, number of i-nodes, etc. But with today's robust technology, we can afford to declare all parameters unlimited because in theory we can afford to offer nearly limitless resources to most customers who choose to host with us.
Selling hosting as unlimited is a way of letting the legitimate consumer know that they don't have to sit and calculate what each parameter does ‐ they can just buy the unlimited package and it will work for them. This is how the industry has evolved over time.