well if someone places a bounty on an entire nation, say, 50m for the death of the SLOB nation, i dont think that could be considered suiciding since it would end up a nation v nation war where one side is getting paid for its trouble
however, i do agree with you that a one man bounty would be suiciding in most cases since if a wlf player had a bounty on his head and died, all of BH would die in return