I had no idea about that. Thanks for sharing that. I will avoid the dyed ones when possible now.
It's not something that people usually talk about. Most of the people I've run into who've used them are monogamous couples who don't like the "mess" associated with sex but find regular condoms to be boring. They're usually using another method of birth control as their main source of protection.
I would just be attacked with a fit of giggles if my boyfriend put on a condom that turned his cock a funny color! Even the regular opaque-ish latex ones made it seem weird for me. Thank goodness we can't use latex and don't have that option ^^;;