There are many dogs. Trained to smell for this or that. Some smell for drugs, some smell for explosives , Some smell for food items in Customs and others sniff out large quantities of cash.
So if an Airport has 10 Dogs and only four are looking for drugs then yes it is true the Majority at that Airport are not drug sniffers.
Now can you tell what the next Fido that goes by is sniffing for?
One Airport may have two dogs and another has 20 every Airport is not the same.
Now the Dogs work the Passenger areas for part of their shift.
They also work out of sight sniffing around. Baggage carts and things you do not see.
Just some basic information. When you smoke have you ever noticed a smoke smell on your clothes?
Fido might not find your stash but he does find your suitcase that you smoked around.
Police can bring their local Drug dogs at any time for a walk through. Airport security is not that concerned with drugs in your pocket. LOCAL Police are.
Airport Security is not the same as CUSTOMS they have their dogs too. They often check out the bags before they get to the customs area.
Customs does not use just dogs to find the bad guy, Customs FIDO can go for walk in other parts of the Airport. They like to smell stuff.
Can you get away with it probably. You just do not know if your flight is the one they decide to pay attention too that day.
I bet you also in your travels did not see the Police Camera Monitoring room or the undercover security in plain clothes wandering around the Airport with you.
You did not see the check made on your name before you arrived at the Airport. You did not see the guy watching you as you arrived on the bus or car outside the terminal. The random check of parked cars in the lot. Did you notice the guy at the Magazine rack that watched you in the security line? Are you doing something that makes you stick out from the others? They way you walk ,stand,move your head,
Is is not a good idea to take bad stuff where you know there are Police looking and searching for the bad guy.
You may or may not be detected. Some reason in particular you do not shop local when you arrive at destination?
ODDS It only takes the ONE dog that walks by you that matters.