Yes and no. Should you have gotten more for the games in general terms? Hell yeah! Should you expect to get more when trading stuff in at a store that wants to buy games with the same retail markup as when they're buying brand new ones at retail? Definitely not.
Like people have said, trade-ins at game stores are a sure fire way to get ripped off (unless there's some crazy special like what Jb-Hifi offered when Pokemon Black/White came out).
Depending on what you have, I might be interested.