So I've removed 'deception' from the skill list. So tired of all the "I'm a bear, and can't speak common, but I maxed out deception so I can bluff my way so that people believe my growls are words in common and that I am a human" joke stories. (It was funny once.)
Instead, we roleplay out social encounters: to say it say it.
Yesterday, a group of green Dragonborn cultists had stumbled upon the party and decided to join up with the party, who didn't want to risk a fight with these dangerous guys so instead, with trepidation, let them tag along. Partly because the cultists had access to Lesser Restoration and other powerful spells (praise Tiamat). Cozy campfire tales, food gathering, soap opera ensued but of course the main point of order was the watch schedule.
Five cultists, five party members. The initial suggestion from the party was that they do five watches, each watch with one party member and one cultist. After a couple of clumsy and easily discovered attempts by the cultists to rifle through the party member's bags, the party said "We're tired of you waking us up in the middle of the night claiming you were only trying to borrow tinderboxes from our bags, you want to light your smokes use the campfire! Let's make a new watch schedule. First watch: me and Fox. Second watch: Ran, Raved and Musharib. Then third and fourth watches, you guys."
I.e. all PCs asleep after the first two watches, then the cultists would have free reign over the camp! Hehehe! Of course we gladly accepted, pretending to be upset that our company wasn't appreciated. Meanwhile, looking over the rules for killing someone in their sleep (advantage + all hits are crits). Heh heh heh…
But… there never was a third watch. The party snuck away and left!!!!
I was just about to say something like 'of course they posted a guard' or 'of course they were listening in on you' or 'of course they were peeking out from their tents' but… I stopped myself. The truth was that I had envisioned the cultists going to sleep, ready to kill the PCs during third watch. That the PCs would leave was the furthest thing on my mind. All I could think of was their sweet, snoring, exposed throats and the cultists' maxed out sneak attacks.
I was fooled. The players had outsmarted their DM legitimately.
All I could say was "You get 170 xp each."