Seto, your opinion is respected but don't disrespect the others just to promote Japanese Technology. American Muscle cars and European cars are also great and it all depends on the consumer what he wants. If he/she wants a crap, light weight car which dis-mantels itself while moving on road..then he/she can choose Japanese cars. Others who like Durable, long life, Heavy Muscle and manly cars..then they can go for something American/European etc..
Have you ever noticed, Most of the old cars still moving on roads are american or european! it is because they have used quality materials not like your japanese low quality products. That is why your cars are light weight and after few miles all the equipments starts giving weird sounds.
Anyways, for modification topic, your point is useless. As it is illegal to modify a car here then why companies should get such ppl who are good in customization/modifications. They are following a standard procedure of repairing. Which is good.
Garage mechanics are not idiots! better you should start learning something about RESPECT!