Seasoning the pan will make it less likely to stick, but will also give it a brownish tinge, so it won't be "shiny and new" looking. And if you ever scrub it with steel wool, you'll have to do it all over again.
Seasoning the pan basically creates a surface of oil that has been baked on so that your food is on that rather than directly touching the metal, so less sticking. It is brownish on stainless (I have a whole bunch of pans that look like that, which annoys the wife, but since I do the cooking, she lets it go) and is unnoticeable (other than the deeper black) on cast iron. Because of the porous nature of cast iron, seasoning is absolutely essential if you don't want sticking...or rusting. Stainless has no rust issue and the metal, although it has surface texture, is not as open as cast iron, so the seasoning is optional.
If you use enough oil when you cook and get the oil hot first, you will not experience sticking problems with an unseasoned stainless pan, but if you are trying to do low fat cooking on a barely oiled pan, proteins, in particular, will tend to stick.