There isn't any, but you're using an extreme example to justify the idea of introducing a law to remove all personal choice from the equation.
To ask it another way, where's the fun in me fitting 16" wheels all around to my MR2 and running bigger tyres for better handling, rather than the 15" front 16" rear fitted by the factory? You're proposing we ban that, just so that we can wrap everyone in a protective cocoon in case a dumb person does something dumb.. and a newsflash: if someone is going to do something retarded, the law won't stand in their way..
In your example, presumably you're bright enough, (i know you are), to use suitable tyres for the application in mind...
Fitting 205 width tyres on an Omega just because the 225/55/16s seem a bit expensive is a rubbish excuse... in that case, fit a set of early steelies which are, iirc, 195/65/15 and probably cost £30 each... but then I suppose they'll look rubbish

I can see where Varche is coming from, but you're sadly quite correct, stupid people will do stupid shit as long as they're alive enough to do it...
Incidentally I saw a bright yellow MR2 buried in a post and rail fence yesterday... didn't look too healthy with bits of body work strewn fifty yards in every direction
