In the 20th Century, there were famous sociologists.
But in this century, economists are much more likely to get publicity, even on non-monetary sociological topics such as crime rates. For example, U. of Chicago economist Steven “Freakonomics” Levitt has a new paper out about how he was right after all about legalized abortion cutting crime. (I haven’t read it, but I wanted to mention it.)
Similarly, Raj Chetty’s popular Big Data analysis class at Harvard is offered under the Econ rubric, but it’s more like a combination of market research data techniques and sociology content.
The reasons economics have been imperializing adjacent disciplines like sociology, political science, anthropology, and geography (with perhaps psychology holding out as a separate, somewhat imperialist pole) are numerous. One is that economists are slightly less neutered by political correctness that academics in other disciplines. Another is that you can make a fair amount of money as an economist, so it attracts the ambitious and practical.
But another reason is that the number of economics majors at elite colleges is bloated by the refusal of most to allow undergrads to major in Business or Finance or some other get-a-job field. (Penn is one of the few Ivy League colleges to allow undergrads, such as Donald Trump, to major in Finance.)
(Harvard, of course, has a famous Business School with extremely well-paid professors, but you have to be about 27 years old to be admitted to the MBA program.)
So, if you go to Harvard, the way you signal to employers, such as Wall Street, that you find money interesting and appealing is by majoring in Economics.
Hence, at many elite colleges, the Economics department is prospering, while other departments are withering. If the other social sciences wanted to cut Economics down to size on their campuses, they would demand the creation of Business majors.