Well, some one else might do it first and then where would you be? Think of your 15 minutes of fame going to someone else! You wouldn't want THAT to happen, would you?

Actually, these fools probably put out the word on the street that they wanted some explosives and a friendly local happened to mention that this guy was looking for explosives so, after checking them out (e.g., past criminal records and such) the Fibbies set 'em up. No entrapment, because THEY went to the undercover cops, the cops did not force or coerce them into anything.

Works that way with most of these things. The REAL bad guys keep their mouths shut and don't trust nobody nohow.