Some low-levels (i.e. Myself) can't afford to buy new cards or can't afford certain cards that go with thier strategy that they're looking for. Course, there will always be people who do just play with whatever is given to them. But you would have to know them to know that they're not going for a specific strategy.
I have to disagree with viva. Some people don't want to spend money.
that's legitimate. and some people would rather win than have varied
game play. that's also legitimate. you seem to be someone who doesn't
mind spending money and would rather have a more interesting and
different gameplay experience. that too is legitimate. but don't get
mad at people because they don't think like you. it's unfair to them,
and, honestly, it's just plain rude. But if you don't listen to me there, at
least, please don't quit games. play the third game out and then blow
them off in the future. It pisses people off otherwise.
Diablo, ELO is basically a mode where a player can't just jam his deck full of 4 and 5 star cards that are all maxed out. Instead you're forced to use mostly lower level cards, with roughly the average max level of the cards in an ELO deck being 3.