Let's see what 1,000,000 means: cost of the troops Archers 60 - Pike 150 and Cat 600
An army of 500 troops I have 280 Archers = 16 800 + 100 Pikemen = 15 000 + 120 Catas = 72 000
For a gold total of 103,800 if I take this amount divided by 1,000,000 = 9.63... So nearly 10 full armies. In addition to the gold that can be found here and there. So the moral does not help your enemies to shave you, captured and also to your friends who may suffer the consequences.
When I'm seneschal, I don't allow more than 100,000 or 200,000 big max for very active players. My pleasure was to watch every 2 weeks and when I found I was making big holes in the villages ;-) I'm not very nice ;-)