Maps can lead to adventure. Or to an enemy's secret hiding place. Or to mystery. Or to a Lost World full of excitement and danger.
But most importantly, to loot.
Commentary by memnarch (who has not seen the movie)
And technically like BB-8 as well. I don't remember when Allan would have gotten the log specifically, but I do know that BB-8 was the third person shown in this episode to have it. Which would mean that log would have had to have been given away at some point in order for BB to get it back. Maybe the curse doesn't care about droids? Or perhaps it's that the Dameron family has a curse of its own, and Lor San was making things up about the logs.
This has to be near the end of the movie now, right? The scene feels like something that would be a part of a TV series to draw the viewers back in for the next episode, except this is a feature length film. Did Disney shoot all of the sequel films at nearly the same time à la Peter Jackson's Lord of the Rings or something and weren't sure about the reception? Disney should have known they don't need cliff-hangers to draw people back in; Star Wars is one of the most popular Sci-Fi series out there.
All that aside, this is a pretty neat looking scene, even if it is a little silly.
Transcript
BB-8: Let me grab Luke’s map.
BB-8: Allan, can you pass me his expedition log?
Allan: If I give it to you, I’ll be doomed! Like my twin, Poe!
BB-8: True...
Allan: Cool! Here you go. {gives BB-8 the log chip}
GM: <roll>
GM: <scribble scribble>
{BB-8 projects a hologram of Luke’s map}
GM: Luke’s map slots into R2’s reintegrated data perfectly.
R2-D2: So we know the way to Ahch-To now.
Leia: You need to go. Find Luke!
Allan: And sweet, sweet ancient Jedi loot.