Er, yes it is. Ask a Greek politician whether or not they had an option not to accept austerity. It was imposed on them by the monolithic entity that sets economic policy within the Eurozone.
Would that your idea of what the EU is were true. Spain is a very obvious example of a country in the EU that has very little say over how the EU is run or indeed over how Spain is run. Spain and other southern-European countries do what they are told by their northern betters. Power in the EU is not distributed per person, but per unit of wealth, and the interests behind most of that wealth do indeed form a very solid monolith.