Why are some non-NEXUS travellers sent through the NEXUS line at Pearson?

Question

I've connected through Toronto Pearson International Airport to the US twice this year, and both times I was directed to the NEXUS lines, even though I'm not a card holder.

I scanned my passport as usual, showed the receipt to the agent before customs, and they pointed myself and a handful of other travelers to the NEXUS line. After we went through customs, the agent before security somehow knew to send us to the Nexus security line, as well. I'm guessing it was because the customs officer stamped our boarding passes.

Does anyone know why the agents do this, or what the criteria for it is?

Answer 1

The airport web site suggests you may be some other sort of priority traveler:

A priority lane will be available for Nexus cardholders and airline guests with priority designations.

NEXUS cardholders and airline guests with priority access may enter the U.S. Customs hall directly at any time by showing their boarding pass and/or valid Nexus card and U.S. Customs card.

This may be because you have a membership with the airline that provides priority access to boarding and other services, because you're flying first class, you are disabled, or whatever other reason the airline might designate you as a "priority" traveler. If any reason applies to you, the word "priority" appears on your boarding pass.

Answer 2

Is it possible your connecting flight's boarding time was near? I've been sent to priority customs/passport/security lines when I had a tight connection - both airlines and airports have strong motivations to ensure everyone boards on time because missing passengers can cause very costly delays.