NYU's case was somewhat forced by financial problems in the '70s. They had been maintaining two campuses for decades (one in the Bronx, and one in Manhattan), and in 1973 sold the Bronx campus along with some of the programs that were housed there (most notably Engineering), to try to sort out the budget problems. Nowadays NYU is overflowing with cash, so was able to "acquire" the former Brooklyn Poly to get back into engineering.