Answer:
short answer
A bad idea, since
(i) they produce CO2 (partly responsible for the rise in global warming),
(ii) there is a limited amount of fossil fuel from which we make valuable materials such as lubricants and plastics,
(iii) fossil fuel resources are finite, so burning them means we are consuming a resource we can never replace, and
(iv) we can actually build new industries and create many new jobs developing renewable sources of energy instead of burning fossil fuels.