Depending on how prevalent theft is in your area, I wouldn’t trust anchoring into asphalt nor substrate.
A bag of cement is cheap, cutting through asphalt is no big deal, it’s easy to dig a hole and you can get some very long bolts that would sink nicely into wet concrete. I would also suggest getting threaded bolts and attaching a few nuts and washers along the length of the bolt before submerging into the concrete - this would give added protection from removal.