That's because riots and such protests are rare in the US; and Ferguson brought new issues to light, not the same old issues.
That's not the case in India. The concept of a "bandh" (close the city and shops, if your shop doesn't comply, you might get beaten up by party thugs) is a common one used by political parties for various reasons. If someone told me that there was a bandh in Mumbai tomorrow, I'd not be surprised, not even really annoyed. One gets used to this stuff.
Riots are a few steps above this, but aren't too uncommon either. Many of them have legit motivations. India is a country of many, many communities and many, many views and it's common for some community to feel aggrieved by something; often rightly so.
This one, I don't think it has a legit motivation either, but I'm not so sure. The reservation system is a rather broken one -- not that I'm saying it should be removed (affirmative action can be quite effective) -- but that it could be improved quite a bit, checking against income and with more safety nets for students/etc who are boosted by this but don't do well. This case seems to be one of people from a non-suppressed community clamoring for reservation, motivated by other non-suppressed communities who got reservation due to a political move (ICBW here).
Thing is, fixing the overall reservation system is a really, really hard problem in practice. There's a lot of politics involved -- anything perceived to weaken it will severely affect your image, and besides, most of these laws need a majority of folks from the relevant minority group to approve them, and due to the way folks vote here, politicians from a minority group depend on that minority group for votes, and if they were portrayed as weakening the reservation system, their political career would be doomed. So the reservation system is something that can only monotonically get worse. Most folks have resigned themselves to this fact.
On the other hand, in Ferguson, the issue is something which the minority group was very aware of, but not the majority group. Many people are now realizing that African Americans look at the police very differently due to the way the police treats them. There's a lot of new information in the system, and there are many proposed solutions, most of which do not qualify as political suicide. It's not the case here, everyone already knows about the issues here, and most if not all solutions are political suicide.
Schools do that, and it heavily favors whites. (alumni/donor preference)
Maybe not exactly what you were suggesting
Of course, it's not as easy as simply filtering by income by setting a threshhold. In some cases you may want a income-agnostic reservation, too, to prevent caste-based discrimination (not so common in cities, but it still exists), in cases where there are strong human elements in the selection process (i.e. it's not just based on the results of a test, but where there are people in the pipeline who may discriminate). This is something that may need to be handled in a nuanced way.
(Not that I'm saying that reservation is the only solution, just saying that if we want to stay within the confines of this system, it can be improved a lot)
[1] FWIW, in India, everyone is technically a minority, though of course not all minorities have been downtrodden. In this specific case a possibly-non-downtrodden (as far as public opinion goes, this group is in general quite well off) minority is requesting special treatment, which is receiving opposition.