For some of us it is a very bad idea to remove our glasses before riding. Let me put it to you this way: I generally have bad memories of breakfast by the time I get to the ride anyway. I don't need any reminders.
Second, on a high-speed ride such as Millennium Force, I would not dream of riding without my glasses additionally because my eyesight is important to me...and I have scraped enough insects and debris off of my glasses over the years to know that I have taken some rides after which I would probably have been blinded had I not been wearing my glasses.
Of course, this is not a problem for me provided that I can use a retention cord...which I have personally found to be a bad idea, but that's just me. So long as I can still ride. The next question is, how picky are they going to be about the strap? Many of the straps out there are incompatible with my glasses because the temples extend down below the back of my ear, so I have to use a cord that attaches to the upper part of the temple rather than one that goes over the earpiece...
--Dave Althoff, Jr.