I won't comment about the lore, since that'd be OT, but IMO suicide bombing in XCom is a weak tactic. You gain little comparing to actually throwing the explosive, and you risk reaction fire. If you have a clear path of approach, melee works just as good (if not better), while allowing the unit to usually survive. While the appearance of completely disposable units like dogs (who are unable to throw) makes actually losing the unit a no-issue, I still think it's much overrated. Priming the explosive takes a ton of TU, and carrying primed explosives around creates a serious risk to your own troops.