That may be true, but it's the way the trade market has become. Atlanta got less talent for Teixeira, and he's arguably a better all around player. Even if Holliday were a top 5 hitter (which he probably isn't because of Coors Field and the protection he had in the lineup) there is no way the Rockies could pay him top 5 money. Nor would they, it is not a good practice to have 75% of a teams' salary committed to a small percentage of the players.
And like it or not, the Rockies are a small-market team. Not because of the market they play in, or their fanbase. Because that is the way their ownership group has behaved for years. They've been more about turning a profit than putting a winning product on the field since they took over, despite which they have had some decent teams. They were burned by past free-agents and decided to go another route, thus avoiding large contracts for the most part. This is just another example they intend to stick to that model. It can be, and has been done successfully by countless teams in the league and not always to the delight of the fans.