Preamble
Around my area (Russia), bow and crossbow energy in LARP is mostly limited by their draw weight, which is around 16 kg for bows and 18 kg for crossbows. However, bows usually have a lot longer draw length than crossbows, e.g. 60-80 cm for bows, which usually is not limited by the rules, and 30 cm for crossbows (usually limited to this length). It often turns out that bows show better energy performance than crossbows. It also takes less time to take another arrow than to reload a crossbow, crossbows are usually more complicated in their design and hence more prone to misfires or other malfunctions.
It should also be noted that while a real bow takes a lot more time to master than a real crossbow, this is not the case with a LARP bow, as its potential is very limited by the "safe" arrows with 35-50 mm wide points.
Problem
So, while bows, despite some of their downsides (e.g. low DPS compared to melee weapons, people not noticing arrow hits and hence not counting them), have their niche as being the best ranged option available in fantasy games, crossbows are very rarely deployed.
This leads to weird situations when armies that would look much more authentically with crossbows (e.g. a dwarven army) don't deploy them.
Solutions that don't work
- Increasing the allowed draw weight for crossbows is most likely not an option due to safety reasons, at least until I succeed at making everyone wear protective glasses like in airsoft, which currently doesn't sound feasible in fantasy LARP. For some unknown reasons, people believe that a helmet is enough. It actually isn't as it usually doesn't protect eyes; for the record, a helmet without glasses can potentially make things worse for the victim, ensuring that the arrow doesn't leave the eye if it hits at a right angle.
- Neither is increasing the damage crossbows inflict: it is usually not possible to distinguish an arrow hit from a crossbow bolt hit. Increasing damage of both weapons leads to bows being more popular, crossbows still being inferior.
- Banning bows for some players by the rules doesn't make them switch to crossbows, they often rather have no ranged personal weapons at all. This has been tested and doesn't work.
- Banning anything by in-game (in-character) laws doesn't work at all. People don't care. E.g. magic is often considered "heretical" by faction 1, but at some point "the conflict is resolved" and faction 1 makes peace with factions that practice magic.
- Providing crossbows for the players is very expensive, providing a lot of those for free is nigh impossible in most situations. Plus, I don't want to spend my time chasing players so that they either return my own stuff to me or pay a compensation if something is broken. I have experience with giving my things to other players (mainly foam swords which I already own in huge quantity), and it is mostly negative.
The question
Crossbows look cool, and sometimes fit in the situation better than bows, but are rarely used because of their practical disadvantages. So, how can I promote the use of crossbows instead of bows in LARP as a game master, bearing in mind the aforementioned restrictions?