By changing it, you would be creating a different start-of-game situation that allows for much earlier MP wars.
Well yes but that's the whole point of an OPTION, which is understood here by most. And there are other scenarios besides 1805 to consider. And with the Editor, players can create customized scenarios that could assume an at-start econ phase combined with otherwise reduced starting forces to compensate. THAT could allow players some flexibility to customize their forces for maybe a little more cav or another ship, or additional corps counters.
Obviously there are some who physically cannot bring themselves to consider anything BUT the plain vanilla classic 1805 EiA 1805 campaign, but for other players the potential for interesting and reasonable variations in this computer game version is very attractive. If you can play using "house rules" and other agreed-upon changes in the board game, why not also for the computer game??