All the good names are taken thats why. Just make all generic terms show a web page of listings related to that term. Like if you type "baseball cards" thousands of listings will come up just like a search engine so you can pick which site you like. Now if you type "edsbaseballcards" that site will load, not the search listings because its not a generic term. No .coms no . nets none of that shit.
Its calle E.O.I. Equal Oppurtunity Internet
No one can sit back and get rich easily with type-in names and everyone will have to work to get traffic