Nah, sikhs are pretty much as exclusive as Muslims in Canada. And besides, how do you know there are not Muslims involved in campus life? Do you have a Towelhead-dar?
In the UK Sikhs are pretty integrated, as are the Hindu community. Of course, you can make generalisations, and there are always exceptions, but my experience pretty much concurs with that of Kaiwai and Cool Canadian. I think the different attitude towards society and life is discernable in the second and third generation South Asians of different backgrounds. Of course these are broad brush strokes, but nevertheless, you can see certain markers that are different.
Its about orientation and attitude. Non Muslim Asians seem to embrace opportunities, and don't reflexively reject or fear British society with the same amplitude as many Muslims do. And I do think an important word here is fear. I think much of what it is, and the relative success of minorities, comes down to how much they fear society.
Another thing that might seem superficial but is in some way representative of a difference in attitude is alcohol. Alcohol is very demonised by Muslim society, as are drinkers. But for better or worse, Britain is a pub culture, a drinking culture. And Hindus and Sikhs are in general relaxed about drinking, and for better or worse, this enables them to mix in society and have less anxiety in social situations. In fact in the midlands and parts of London, many pubs are owned by British Sikhs and Hindus, and these are in multi-ethnic areas.
I'm not saying this is the only thing, the only marker, and I'm not nessecarily criticising per se Muslims for not feeling at ease in this part of society, but it is an observation.