Is it impossible to steal Maria from Benny when you first meet him at the Tops Casino?

[Pumba]

I absolutely can't steal his damn gun, even with 197 sneak skill. I make sure I am hidden and have even tried planting better guns and ammo on him. Every time he catches me he starts his scripted conversation with the player.

[Rez Elwin]

You can pickpoket him while at the Fort when he tied up, at least I know that for sure, might not work in the Casino.

[Scheneighnay]

I'm pretty sure all scripted conversations are like that.

[Big [REDACTED] Marty]

Just bring him back to his room, give him a foot job, merc him, then take his gun in the morning.

[Luis the Uma Loving Wizard]

Or if you suck, engage him in combat when your in his suite, use V.A.T.S. To target Maria and hope you get a critical hit on it. Now it’s a matter of grabbing it before he does. Then you can do the “Talk about owned” GRA challenge (Kill Benny with Maria).

[DainBramaged4lyf]

Perhaps one way to get Maria off of Benny is from a how to vid I saw on YT. Let Benny get away to end up at Fortification Hill. Take a stealthboy with you and when Caesar offers Benny's life go ahead and use your stealthboy, crouch and go behind the effing snakey bat rastard, attempt to lift Maria from him as it should be the only thing on his inventory, load up some hollow points and drill his sorry ass. No hostility from Caesar or his praetorians. A lovely "a fair kill" shall be murmured.

[Johnny Casey]

Even if you get him to the Fort when Benny is kneeling and you have the chance to pickpocket his own gun, it is quite impossible to do so, due to the ridiculous chance to successfully pick-pocket an item in this game.

The full story behind what exactly is so wrong about this pickpocket mechanic can be found here[forums.nexusmods.com], although it is a large one to take it in one-go. Long story short, Thanks to Maria's item value of 999, the chance of successfully pickpocketting the gun is nearly impossible.

Just another thing that Obsidian have screwed up when they were making this game. Not a surprise.