Why should we care about our privacy?

Every body always advocates for privacy but I have yet to found a real answer to why should we actually care so much about our privacy especially if the problem faced is real advancement or creating a society where we are all safer. As an example we have many laws which limit the police and government in the why they can get evidence, many of these laws are in place in order to protect our privacy, why shouldn't we allow the police to get what ever information needed in any way they need ( as long as they don't hurt any one in the process), this could create a safer environment for us all.

Just as a side note I am not talking about giving up our privacy for private corporations to make profits in (I.E Facebook, Google etc) but only to causes which can improve the human race and society such as DNA reasrch, police and othets