I asked Smarthome why they dont sell plain white un-engraved buttons for their Insteon keypads (they only sell the clear ones, or white with A,B,C,D engraved). To replace all my buttons with white would cost close to $1000 dollars, (for crappy little plastic injection molded buttons that cost about .01 cent per 100 buttons to manufacture). I'm really pissed. Here was their response:
Hi Richard,
Thank you for your email. Whoever helped you was absolutely correct. You would need to purchase the Custom Etched buttons if you wanted "blank" buttons. Unfortunately, they are $49.99 a set, not $5.49 like the clear ones. We don't have an official recommendation for removing the lettering from buttons. One thing you could try is to use a Dremel tool with the polishing tip.
I hope this helps.
Thank you, Sam Smarthome, Inc.