I recall two potheads damn near sleeping at a major intersection traffic light. It is true as the county sheriff was a neighbor of mine, and; he arrested the driver. The driver was so stoned he was talking about colors. That was 1978.
Frankly I disagree, and; the US army alone has a large fort in CO. I would probably close the Fort down or make the state off limits. With the losers Obama has thrown on the military I bet that Fort Carson becomes a real popular place, plus commanders will be involved in UCMJ actions often there.
They were creating a hazard and operating a vehicle while impaired. Both good reasons to arrest them. Whether they were drunk or stoned should be irrelevant.