Popular struggles don't end with the establishment of democracy, they are an integral part of a democracy because de mocracy evolves through popular struggles.
The case of Bolivian water war describes this:
When the World Bank pressurised the government of Bolivia, which is a poor country in Latin America, to give up its control of municipal water supply, the government sold these rights for the city of Cochabamba to a multi-national company (MNC). The company immediately increased the price of water by four times. Many people received monthly water bill of Rs 1000 in a country where average income is around Rs 5000 a month. This led to a spontaneous popular protest.
In January 2000, an alliance of labour, human rights and community leaders organised a successful four-day general strike in the city. The government agreed to negotiate and the strike was called off. Yet nothing happened. The police resorted to brutal repression when the agitation was started again in February. Another strike followed in April and the government imposed martial law. But the power of the people forced the officials of the MNC to flee the city and made the government concede to all the demands of the protesters. The contract with the MNC was cancelled and water supply was restored to the municipality at old rates.