I would not say that 25+ is old, but I would say that it is slightly older. Slightly older than the people typically interested in a "fratty" culture.
John William Meriwether - born August 10, 1947
Myron Samuel Scholes - born July 1, 1941
Robert Cox Merton - born 31 July 1944
I said that I think that people interested in fratty culture tend to be young.
Beanbag chairs and a constantly flowing keg are not meant to attract older talent. Certainly there are some older people who are attracted to that type of climate, but that really is not the target audience.
Not everyone who works at a hedge fund comes from the cast of Boiler Room. Talk about painting people with the same brush...