After a while it clogs up the sewage system. Waste on the road is quite smelly, too. I've seen people cover their nose and mouth with cloth when walking by piles of trash. The missing and broken slabs on the ground also pose a threat to Indians that are blind or physicially disabled. These consequences are very real and fortunately there are people who wish to change it.
So again, I want to remind you that Bengaluru's sidewalks aren't all the same. In some areas, the smelly impediments are more or less nonexistent while in other areas sidewalks are nonexistent. It all seems to depend on the means of the people living in a given area of the city. But for the worse-off areas, there are efforts to change the sidewalk situation as a whole.
For example, there's an effort to persuade Indians to throw waste in a designated bin, some of which promote recycling. Indians have used cute animals to promote throwing waste in the garbage can. If less people throw waste on the street, it's possible Bengaluru can improve a huge portion of its sidewalks.
