For Colorado's groundbreaking retail pot market, lines have been long and sales brisk since Wednesday when the state became the first in the U.S. to allow legal marijuana sales to anyone older than 21.

At Lodo Wellness in Denver, there were plenty of customers and product - all smokable and drinkable.

"Since we opened, we've had a line to the corner that hasn't stopped," LoDo Wellness owner Linda Andrews told ABC News.

At one bakery, pot was also edible.

"We take the marijuana plant and we infuse it with regular butter," Chef Hope of Love's Oven told ABC News affiliate KMGH in Denver. "Tastes like homemade, like you'd want to eat at Grandma's - but not quite like Grandma's cookies."

Related: Colorado pot buyers in high spirits lining up for legalized sales.

The pot boom has created jobs - the National Cannabis Industry Association estimated that nearly 10,000 jobs had been directly created in the state by cannabis-related companies - as well as growth.

The state is expected to haul in $67 million in weed taxes a year.

"The industry has certainly grown in the last year, but the medical marijuana industry was already fairly well-established in Colorado," said Taylor West, the association's incoming deputy director. "Certainly many of those existing businesses have added staff in preparation for increased demand with adult use. Staff numbers for individual companies range from the single digits all the way up to 300."

Take a hit: A stoner's guide to legalized pot sales in Colorado.

All around downtown Denver, though, warnings were also sprouting up as pot critics warned of the plant's downsides. Authorities said they were worried about more people driving stoned.

"Marijuana impacts your judgment. It impacts your ability to react…. If you're impaired by a substance, you can't drive. End of story," said Tom Raynes, executive director of the Colorado District Attorneys Council.

The federal government still considers pot illegal and today John Walsh, the U.S. attorney for Colorado, said the state's system "is still very much a work in progress."

The Justice Department also said in a release in August that it would not look the other way if teens started using pot, if drug cartels became major players, or if weed started crossing state lines.