The roads are not necessarily owned by the local authority, they just have the right to use it as a road.
Most roads started out as private land. At some point the road was adopted by the local authority. They can then define a highway boundary which is the land they have legal authority over. This can sit on top of existing ownership, who can retain the freehold.
You just see gaps because the owner decided to register the plot. The land registry will then try and guess where the highway boundary is, and sometimes get it wrong. But it is perfectly possible for the road to revert to the freeholder if the highway is removed.
Most roads started out as private land. At some point the road was adopted by the local authority. They can then define a highway boundary which is the land they have legal authority over. This can sit on top of existing ownership, who can retain the freehold.
You just see gaps because the owner decided to register the plot. The land registry will then try and guess where the highway boundary is, and sometimes get it wrong. But it is perfectly possible for the road to revert to the freeholder if the highway is removed.