I think people do occasionally crack steel frames, but it is rare. Perhaps unsightly rust, as well as paint chips/scratches are a bigger issue. Road Salt?
More common one will find dents in the paper-thin steel tubing, many of which have no structural implications. On the other hand, what might be a small dent in steel could be an expensive CF repair.
Steel (or Titanium or Aluminum) can be repaired including roadside repairs. The problem is that very few frames justify the expense of a tube replacement or such, although welding can be cheap if one finds a way to get it done. And like CF, a repaired frame should always be considered "repaired", even if it is as good as new.