We bought really cool red-framed safety glasses in bulk for the 2006 season (found good selection and prices at
www.safetyglassesusa.com). They really can become part of your team's uniform.
Safety glasses are indeed available with a wide variety of presecription strengths (e.g.
www.duluthtrading.com) for contractors, etc. They may not be exotic presecriptions, but basic 2X cheater magnifiers.
Safety glasses are like seat belts. yes, they're REQUIRED by a FIRST rule, but after a while they become automatic just like seat belts in cars. There are so many things going on that it's just stupid to risk even one accident in the pits without safety glasses.
I can't even go to my factory at work without safety glasses even though I'm 20 feet away from anything walking the aisles.
At FIRST, we also need to be good and teach this lesson to the younger FLL kids that come and visit our pits...it sets a good GP example.