There are start up's where you do not have to sell 100 troops, and at turn 99 you have just as many cs, ent/res/indies/farms whatever - and 100 troops more than the other guy.
The 100 troops more or less will not be the difference between 1st and 2nd, but it can be the difference between 88th and 89th.
Them 100 troops are you're loyal followers keeping the population in check. Sell them you'll be overthrown by your unchecked population (Changes planned for next set... Honest).