People are weird about Los Angeles' Eastside/Westside thing. The same wannabes from Midtown, Hollywood, Silver Lake and Echo Park that throw up "W" hand signs and exaggeratedly say, "West-side" when they're ironically enjoying rap music are the same jerks that claim, despite the fact that they live in Central Los Angeles, that they live on The Eastside. If you call them on it, they usually claim that the real Eastside (the communities east of the Los Angeles River) are all East Los Angeles -- which is incorrect but more likely a sign that they've never been to the region that they claim -- and not some willful act of subterfuge.
THE OTHER EASTSIDE
To be fair to these noobs, ill-informed Westsiders, transplants, and weirdos who insist on dividing the entire city or county into just two regions (I count 20) -- there is more than one Eastside... sort of. The other Eastside is sometimes referred to as the Black Eastside (even though it's currently mostly Latino) and has a long claim to the Eastside name. To many black Angelenos and South Los Angeles residents, the traditional division between the Eastside and Westside is the 110 freeway (and before that freeway's existence, Main Street). However, when "The Eastside" is used in this respect, it's implied (and usually understood) that one is talking about the Eastside of South Los Angeles.