Why even bring property rights into the picture, it doesn't change the ownership of the property.<quoted text>
Property rights are granted by the society through the government. One of the most significant of property rights is the right to exclude: "keep off". If the property is zoned for eg., farming, the farmer is entitled to the benefits derived therefrom. If it's urban property the owner might not be able to keep a rooster on his land, it is not his right. You don't own the land; as owner you are the recipient of a set of rights which attach to the res.
BTW, fair market price under eminent domain is often a joke. I have seem instances where a big business in cahoots with a city partake of a land grab, the city gets what it wants, the business gets what it wants, and the property owners get screwed.
If one didn't own the property it could be taken without any compensation.