Chris,
Sometimes they come as stripes too. I had a 'Silverine' seedling years ago that was probably the most consistent at doing this sort of thing. I even named it 'Stars and Stripes' but decided not to introduce it as it didn't do it on every rosette, sort of like 'Fame Monstrose' being more just 'Fame' a lot of the time. Helen wanted her plants to be consistent so this didn't fly with her either although she found the mutation interesting.
My clump of 'Bedazzled' has several that are identical with the bumps on your leaf although I have never noted that cultivar doing it before. probably a bit of genetic potential + the right environmental triggers.
Hope that helps!
Kevin
