Matchmaking matches you with people of roughly the same skill level, so someone playing online does not mean they will necessarily play good opponents. There are lots of people who understand nothing about Dominion strategy and if you are someone who understands even basic Eurogame strategy, you will never be close to being matched against them.
It is obvious looking at Chase's post history that when his profile says he is 13 years old that this is accurate. I fully believe Chase has games against his parents where he gets to build up to buy his ludicrously expensive custom cards and still wins.
Chase, I enjoyed reading your cards, another great set along the levels of Dominion: Gunpowder.