John Oliver: Gary Johnson and Jill Stein offer 3rd option -- like parking lot trash outside KFC/Taco Bell

American voters are pretty dissatisfied with their choices in the 2016 presidential election, and John Oliver said that has driven some of them to seek another unappetizing alternative.

“Americans are so disillusioned by the major party candidates it seems many would prefer to vote for Kevin Kline’s character from the movie Dave or the ghost of Martin Luther King, Jr. -- assuming he only said the three quotes that white people like,” Oliver said Sunday on HBO's "Last Week Tonight."

“This disenchantment may explain the high interest in America’s third parties, because when your two main options are depressing, any third choice seems good," Oliver added. "If you’re in a KFC/Taco Bell and you see a bunch of pigeons eating something in the parking lot, you might well think, ‘Hang on, what have they got over there?'"

Third-party candidates Gary Johnson and Jill Stein are drawing some attention from voters -- particularly those ages 18-29 -- but Oliver said their proposals weren't too strong.

Stein, who's polling at about 2 percent nationally, has proposed canceling the $1.3 trillion in student debt through quantitative easing, which she has described as a "magic trick" that could distribute up to $4 trillion in "free money."

“No, it isn’t, though!” Oliver said. “It is a very complicated monetary policy tool, and while it might not be important for most people to understand it, you certainly have to -- and I don’t think you do.”

Stein also claimed that the president had the authority to cancel that debt using quantitative easing -- but Oliver strongly disagreed.

“That is absolutely wrong," he said. "The president does not have that authority, only the Federal Reserve does -- and it does not take marching orders from the White House because that would be extremely dangerous. You don’t want to give presidents the power to just create new money whenever they want it.”

He's also alarmed by her "strategic vagueness" on a variety of issues, such as Britain's vote to exit the European Union, whether she believes vaccines cause autism, and 9/11 conspiracy theories.

“You can’t just hear a conspiracy theory, fan the flames and walk away,” Oliver said.

Gary Johnson, “best-known of the lesser-known” candidates, isn't much better, Oliver said.

“He has been polling around 6 percent nationally, which is pretty remarkable, given that his race has been largely notable for moments like not knowing what Aleppo is, not being able to name a world leader he admires, and whatever it is he’s doing here,” Oliver said, showing the Libertarian candidate sticking out his tongue while talking to an MSNBC reporter.

"I'm not sure if he was doing that with his tongue on purpose, or if Gary Johnson's tongue just decided, 'F*ck it, I'm done,' and tried to escape through his mouth," Oliver said.

He supports marijuana legalization and opposes the death penalty and civil forfeiture laws, but Oliver said some of his policies are troubling.

Johnson opposes minimum wage laws, government action on climate change, and the existence of the Department of Housing and Urban Development and the Department of Education -- and he also wants to eliminate the federal income tax and the IRS and impose a 28 percent federal consumption tax on everything.

But tax policy analysts have dismissed consumption tax proposals as ludicrous, with most of the burden falling on middle-class families and heavy government spending to keep poor families from becoming even more poor.

Johnson hasn't even been willing to defend his proposals, Oliver said, but instead flip-flops during interviews or begs out of discussions to avoid going to deep "into the weeds."

“The more you look at Gary Johnson and Jill Stein, the more you realize the lack of coverage they complain about so much might have genuinely benefitted them, because their key proposals crumble under the slightest amount of scrutiny," Oliver said.

Oliver said he would love to see a "perfect" third-party candidate, and he understands that candidates like Johnson or Stein could help promote important issues or creative solutions -- but that's not what these two are doing.

"There is no perfect candidate in this race, and when people say you don't have to choose the lesser of two evils, they are right -- because you have to choose the lesser of four," Oliver said. "Anyone who goes into a voting booth on Nov. 8 and says, 'I feel 100 percent great about what I just did in there,' is either lying to themselves or did something unspeakable in that booth."