social culture at Lehigh?

It’s a reasonable concern. A number of small liberal arts colleges in the northeast have eliminated fraternities, sororities, secret societies, etc. due to concerns about excessive partying and other issues. I think Williams was the first; they phased out frats around 1970, as they went coed. At the time, this was a radical and controversial move, but today it’s not unusual for LACs to do this. It’s not an easy change; many LACs have frats that have been established for 100+ years.

In contrast, there doesn’t seem to be much movement in that direction at Patriot or Ivy League schools. Their greater size probably has something to do with this: they are typically big enough that partiers and non-partiers can each do their own thing, without getting in each other’s way.

The current Lehigh administration appears to be taking a hard line on excessive behavior, as per this other recent College Confidential thread:

http://talk.collegeconfidential.com/lehigh-university/1964634-lehigh-seems-to-be-on-top-of-pledging-shenanigans.html

It may not be a coincidence that the current president of Lehigh went to Williams in the 1970s, shortly after the frats were abolished there. In other words, he personally opted for a non-Greek undergraduate environment.