Good afternoon. The Cable Co may be acting outside the law. In most neighborhoods there are utility easements, which include cable companies. If they are running markers and flags across your front driveway and lawn it is likely that they do not have an easement running through your front yard and driveway. They probably have an easment on the property, but it it must likely in the rear of the property, and runs across all the yards in your neighborhood.
However, iif they want to run cable lines, they cannot go outside the easnent, and if they excavate they probably will need a permit.
You should check your deed and property records filed with the county to see if there actually is an easment recorded, and where the easment is located. Some easments are not recorded, and state statute gives utilities rights. So you will need to do some checking to see how it's done in your area.
If the cable company does have an easement, they have the right to enter upon your property to access the easement, but they can't lay cable outside of the easment. Keep in mind that if they do have a legal easnent, then attempting to block them access across your land to the actual easment would put you in the wrong.
If there is no easement, you'd have a civil claim for trespassing and damage to sue for.
I hope this helps with your question.