I highly doubt LE is profiling %80 of packs coming from canada. packs are landing from talking to CA vendors. I wouldn't be paranoid just be sure to continue your OPSEC and we should all be fine.
More current info that echos the same idea http://forums.redflagdeals.com/mail-processing-canada-customs-slow-711375/
These fkn postal workers. I went to university and my job requires a skill few have and I still make less than someone that works 4 hours delivering mail.