Some sectors tend to get regulated as utilities rather than businesses, because they tend not to lend themselves to competition. Railways are a classic example

Some sectors tend to get regulated as utilities rather than businesses, because they tend not to lend themselves to competition. Railways are a classic example; two railways rarely directly compete with each other (since even if they connect the two same points they probably do so via wildly different routes) and some level of coordination is needed to avoid scheduling conflicts on competing trains.