Why Can't We Access Our Own Data?

Today, many if not most people understand that we are under constant surveillance in one way or another, whether by a public surveillance camera or our own cell phones.  What if you wanted to start collecting that data on yourself?  From the New York Times:

OUR mobile carriers know our locations: where our phones travel during working hours and leisure time, where they reside overnight when we sleep. Verizon Wireless even sells demographic profiles of customer groups — including ZIP codes for where they “live, work, shop and more” — to marketers. But when I called my wireless providers, Verizon and T-Mobile, last week in search of data on my comings and goings, call-center agents told me that their companies didn’t share customers’ own location logs with them without a subpoena. . . .