They are still there but you'll only hear traffic on them if a user on the Portland system is monitoring that channel, otherwise incoming radio traffic is not received. I can't recall a single time that Wasco County has been used since reception is greatly diminished once you cross the Hood River county line. Radio coverage is decent into Marion County but the Portland system rarely uses it since Portland will usually turn things over to OSP that head south on I5.
There are many more patches in the system, but the existing radios are limited to 160 talkgroups, not including simplex, and in-county police channels take up around 60 of those. Include a few dozen fire channels, city maintenence channels and other government channels and your fresh out of open slots. In other words, most of the patches in the database are simply there as placemarkers for future use. 785 is the total # I believe.