well, who said 'lucknowi tehzeeb' is a part of Islam, or worshipping dead is a part of islam. Prophet Muhammed(pbuh) did not taught us all this.
So dont judge a car by the driver, if the driver is not good at driving it doesnot mean that there is a problem with car. Similarly dont judge islam by seeing muslims. To know about Islam go for sahi Hadith n Quran. You will know how pure, complete and perfect Islam is!!