you pays your monies, you takes your risks.
to go on track thinking nothing could go wrong is very nieave. i track my cars but i must admit i don't like to push to the limits; it is my daily driver and i'm by no means the best driver in the world. so i'd rather play it safe and have fun, than be riding the limits and **** up. fo rthat reason i feel comfortable with just a crash helmet. the standard protection in most cars is adequate for my needs. i'm lucky to see 1 trackday a year. its just getting so expensive.
if your a more serious track warrior then either a dedicated track car, or fitting a cage would seem like a good idea. i'd love to have a track only car, it would take the worry out of the back of my head thats always there, but then that same thing is what helps keep me sensible on the track.