Most likley because we have an extremely low gas tax that provides abysmal funding for out state roads. Because of TABOR, our gas tax hasn't risen since the early 1990's. This is because state Congress cannot put new taxes on the books without a majority "yes" vote from state citizens. Coloradans generally hate the idea of raising the gas tax so the measure about raising it either dies in committee or gets voted down by we, the people. This leads to the state charging abnormally high registration "fees" to compensate for the lack of a gas tax that helps comprehensively fund the state road budget. Because it's a "fee", the state does not have to seek voter approval and sets the fees however high they please. Colorado is one of the States that doesn't allow that fee to be rolled into the car loan and demands payment in full usually a maximum of 60 days after purchase.

Welcome to Colorful Colorado.

Edit: oh and btw, you'll be paying that probably for the next two years to come so save up.

Just had to redo my test after 10 years this past week. Literally drove in a big circle through a neighborhood. Vastly easier than my master drive test years ago. I'd practice on busy roads just to be safe and have that comfort though.