Gold Generation (Runes & Masteries): Concerns / Questions

Why is it that gold generation runes don't start generating once the game begins? All other players start with their other runes and masteries immediately, why is it that gold generation runes / masteries have to wait until Minions spawn in order to begin accumulating? I know that is a small amount of gold, but considering that these are typically run on supports, a little bit of gold goes a long way.

I feel at the very least we should be back paid for what we would have earned if there is some sort of concern about waiting in base for those first few minutes to gain extra potions.

Also why are there no flat Starting Gold Quints? like 50 starting gold per quint or something? Seems like it could be a logical way to bring more diversity into the starting game, especially for early level / high risk champs.