Why would my bike shop do this?

[VeloVT]

Pitching over the handlebars can be easily avoided by proper weighting/locking your arms when you use your front brake. People who advocate using the back brake only/first in an emergency have apparently never experienced the pleasure of a back brake skid and associated fishtailing, which is not nearly as easy to prevent as an endo. Fun stuff. If you have steady nerves you can usually get out of it and avoid a crash, but for a newbie or someone who is prone to freaking out, it can certainly cause loss of control.

So I say front brake is the one to reach for in an emergency. But of course, you still need to know which is which.