I never cared for groups like Jimmy Eat World, MGMT, We The Kings, or Death Cab for Cutie. Pretty much any of todays Alternative if you can call some of these bands this. There are exceptions such as The White Stripes, The Raconteurs, or The Strokes. Let me show you how Alternative has changed (based on what record companies consider Alt):
Although New Wave wasn't really considered Alternative, it was an influence on it.
Yes Grunge is a sub-genre of Alternative.
You will be surprised! This group although a much heavier rap influence, stations will consider it Alt!