Play video content EXCLUSIVE TMZ.com

Farrah Abraham's under the impression she's making some kind of humanitarian effort with her lawsuit against MTV's parent company, Viacom ... or so it seems.

We got Farrah leaving Craig's in WeHo Thursday night and talked to her about MTV kicking her to the curb shortly after she met with one of its honchos ... whom she says was hostile and threatening.

She says every celebrity has a sex tape, so getting the boot for hers is grossly unfair. She adds Viacom should be worried ... very worried.