The only truth you will find is there is no truth, whether on the internet or outside of it. People will only be truthful if it profits themselves, otherwise expect a lie.
To answer your question; it's easiest to lie to anyone and everyone, to do so all you have to do is believe your own lie. Perception is reality.
People think lying is terrible and to be a liar you're bad person, most of the time though people lie to spare others feelings, or defuse a tense situation, yeah a lot of the time it's because they can or they're covering their own butt to not get in trouble.
To only tell the honest truth makes one unlikable and to only lie makes one untrustworthy. Somewhere in the middle is where the great majority of people live.