It's probably because Rasmus Lerdorf graduated from the University of Waterloo and it's assumed it was developed during this time.  There are a number of these tidbits that are circulated promoting UW, this being one of them.  

My favorite is that the Women's (Gender) Studies program at UW is the largest in Canada.  While other universities such as McMaster and McGill are closing down their respective programs to new students, UW is still going strong.  Producing feminists with pseudo-degrees en masse is often overlooked or ignored.