I found that this wasn't the exact reasons they had for biking were they did -

The headline they employed, which they later changed — “Millennial Couple Bikes Through ISIS Territory to Prove ‘Humans Are Kind’ and Gets Killed” — and other phrasing may have created the impression that the couple’s deaths were infused with irony and served as a kind of allegorical warning about cosmopolitan, liberal naivety:

A progressive young American couple was killed in an Islamic State-claimed terrorist attack last month while on a bike trip around the world … Throughout the trip, the couple embraced the kindness of strangers and sought to demonstrate that people are inherently good.

“You read the papers and you’re led to believe that the world is a big, scary place,” Austin wrote. “People, the narrative goes, are not to be trusted. People are bad. People are evil.”

“I don’t buy it,” he continued. “Evil is a make-believe concept we’ve invented to deal with the complexities of fellow humans holding values and beliefs and perspectives different than our own … By and large, humans are kind. Self-interested sometimes, myopic sometimes, but kind. Generous and wonderful and kind.”

So...

Based on their own written reflections posted during their trip, Austin and Geoghegan were not acting as liberal, idealist missionaries, despite the impression that the Pluralist headline might have created.

[snopes.com]