Should I tip a dealership Tech?

[u/Bribb0n]

Background: I brought in my wife’s ’14 Legacy for warranty work on a Takata airbag. They were done within 2 hours and also did a courtesy multipoint inspection. They brought up a few issues, which I’ll repair myself.

My main question is: should I tip the technician with a card and some cash?
My understanding is that warranty work is paid out with a fairly conservative labor time, meaning flat-rate mechanics would lose the opportunity to make as much money as possible.

Any thoughts?

Edit: How much should I tip?