Most online dating sites have localized page content that attempts to draw in those searching Google/etc. locally (e.g. “Toronto Jewish singles” or “Toronto Jewish dating”). In most cases, these pages are programmatically created and are essentially a large browse directory that follow the lines of dating profile parameters (e.g. pages created that are organized by city, religion, etc. and usually with a mix between them all as well).
Ahhh, one of “the Major” online dating services, eHarmony, apparently likes to help their (formerly) owned sites manipulate the Google algorithm. How? Check out the “Some sites we like” listing near the bottom-right of the eHarmony Advice posts: