Because the majority of roads nowadays in use were built in 1830... /sarcasm

Here, even 70 years ago, several roads were just a dusty path through fields and many of them didn't exist yet. When they were actually built as a road, it was done for cars, buses, trucks and it was done from steep consumption taxes on gas and later from country-wide toll imposed on cars.

Of course, YMMV in your country. But I really think that you didn't have asphalt-paved 10 m wide roads 180 years ago.