Intelligence is like this. You piece together seemingly random information from several sources. A tells he ate pasta on Wednesday and you know he had dinner with B because B withdrew money from an ATM next to an Italian restaurant before B's partner phoned B, who, after two hours, bought a bag of diapers on a convenience store on the route between the said restaurant and B's home.
What you're talking about are details. What I'm talking about is very coarse statistics. If you knew I spent $1000 on restaurants last year, what would it tell you about my meeting with B? Probably nothing.
