I think if you go back far enough, Hinduism is a very inclusive tradition. India is a very geographically diverse and fragmented subcontinent, and so it's long been broken up into lots of different subcultures that diverge and meet up again, and that's led to a rich ferment of ideas over history, lots of syncretism and hybridization of belief. That's how they ended up with such a humongous pantheon -- thousands of local deities being merged together into one big syncretic mashup. That same diversity has also spawned new religions like Buddhism, Jainism, and Sikhism out of the mix. There are even Hindus (and Buddhists) who have no problem incorporating Judeo-Christian ideas into their faith, such as believing that Jesus studied under Krishna or Buddha during the period of his life not covered in the Bible, or even that he's an avatar of Vishnu (or of Krishna, who's himself an avatar of Vishnu). Naturally there have been periods of consolidation and conservatism, as is true in any religion, but there have been periods of great inclusiveness and philosophical ferment as well. Over the broad sweep of history, you can't really say that either is the norm or the exception.
And even if Hindu monks wear saffron robes, Jasminder Choudhury is hardly a monk. Most Christians don't wear priest's collars or nun's habits, so why would any given Hindu or Buddhist be expected to wear a monk's robes?