In Bangalore, the rents are very High ! Plus If you need to rent a house, you will have to pay 10 months of rent as security deposit and also bear the electricity/ water bill Charges. And food has to be cooked by you ! For students / working professionals , it may be difficult to meet these expenses. But in Paying Guest (PG), you just have to pay one month rent in advance and you can move in with your baggage. You get a fully furnished Room with LED TV, WI-FI, Food, Washing machine, etc etc.
So staying in PG is preffered over a House or Room.