It costs at least 50¢ per mile to drive. Plus the toll heading east if you take the bridge. Plus the time to drive.

After you figure the fiscal cost of driving then it’s “just” a matter of the time/effort value to you the ferry provides of its not the outright winner on the cost calculation alone.

If it’s a wash I’ll usually take the ferry to avoid the driving hassles and risks. I’m also more likely to ferry east and drive west.