[tpunx99GSX]

If they made a viable solution yes it would put a couple people out of a job. but it would possibly cause those same people to live a lot longer due to there not being poisons in the air from smog.
Think about this:
Creating an invention to turn a normal car to run on water would not only affect transportation but think about electrical energy. You could therefore take the same hydrogen solution and put it on an electrical generator. Bam no ore electric bills
With saving those two major bills you would have enough money to buy more things (consumerist society) therefore the need for manufacturing jobs would go up and truckers would just have to change from oil and gas to shipping products. Althogh with the amount of products that are oil based the oil truckers will never be fully out of a job along with the oil workers. But they will be able to make more of a profit due to themselves not having to pay for gas.
Overall creating a car to run on water would benefit humanity and out planet, so why stop it.