I've often got bad service from "service providers" - hotels, restaurants, phone services, Internet services etc. I guess that's due to the population in India. If one customer goes back unhappy that doesn't really make a difference, because there would be hundred others already waiting in the queue.
You, as a, service provider would get your share of customers and profits, no matter how bad you are. Thanks to the population.
One solution could be, to write about the bad service you got from a provider and make people aware of it, but often there aren't enough options, for others to choose from. Inevitably, the bad service provider is going to get some customers. What's the way out?