So the Romulans can figure out warp drive, but somehow razor blades, needles, and ink are beyond them?
You know the rule: if it wasn't shown on screen it didn't happen.
Including bowel movements.
For one thing, Nero and his crew have them--the make-up is just more subtle than it was on TNG and DS9. Second, we've seen Romulans without forehead ridges in the 23rd century (both Star Trek as well as TFF and TUC). Third, we've seen Romulans with forehead ridges in the 22nd century on Enterprise. Fourth, we saw Spock blending into a crowd of Romulans in "Unification," despite having no forehead ridges. It stands to reason, then, that there is some variation of the ridges among Romulans.
Also, Nero's wife has noticeable forehead ridges of the TNG class.