Alas, no, my level 105 hunter doesn't have a trinket that procs any sort of attack. I did, however, see a post on the Blizz bug forum from another Marksman hunter, and I can confirm this from my own testing -- Beast Lore generated aggro when a weapon was equipped. The hunter in question tried equipping both Thas'dorah and an heirloom bow, and it aggroed the beast he/she was Beast Lore-ing. Without a weapon equipped, it left the beast alone. The original bug post is nine days old (honestly, no idea how long Blizz typically takes to respond to bugs), but I added my own experience to that post in the event it helps.
tl;dr, heads-up to MM hunters?