you didn't read the term "simple"

buy tickets?

this is not the PoS i know. even lisk and waves are more simpler than that!
Understandable, I guess. My only comment: PoS as it's implemented in DCR isn't the same as in other coins, and can't really be thought of the same way. New coin, new terms, new things to learn.

Also I would mention, the Tickets are what make Governance of this coin uniquely possible.
simplified;
If you just buy reprice and sell, you don't hold long enough to want tickets, therefore no vote in governance.
If you want to invest in this coin, then you are buying tickets (to build "interest" per se), therefore you have a vote in governance.