They probably didn't include the Army because they DO own horses.
PS - Why do we get 14p per mile when travelling by bicycle and only 10 more when travelling by car? I know that bikes these days can be very gucci etc, but are they only 10p apart when you take account servicing, insurance, etc etc?
I suspect the answer is that it encourages more Carbon neutral commuting. Jolly good; I will now set off on my bicycle to a meeting at a secret airfield in Somerset in my uniform. Of course, the meeting is not until next week, but I am a slow rider and mustn't exceed 6 hrs in the saddle a day (H&S you know). I should be able to claim overnight subs because I can't get there in one day, and laundry allowance to get my uniform smartened up after the messy road. All in all, the claim will be substantially higher than if I had taken my car.
Failing that, leave the car and use a Hire Car if that is convenient to you. If it's duty travel, refuse to use your own car.