Do you guys complain at, let's say Amazon as well, when you buy something and it turns out it is for sale 3 weeks later?
It's how the world works people, sometimes you get lucky and you get a great deal, sometimes you are less lucky and you miss out on a deal...that's why they are called deals in the first place.
Riot is making this deal retroactively from October 1st so it's not like they are not trying to include as many people as possible, but they have to draw a line somewhere don't you think?