Hundreds of other people have found work on the edges of the industry. They sell water systems, soil nutrients, lighting and accounting services, like the 19th-century merchants who profited by selling picks and shovels to gold miners. There are now dozens of marijuana-related mobile apps, marijuana-centric law firms and real estate agents, cannabis security experts (it is a risky, virtually all-cash trade) and marijuana-themed event promoters offering everything from luxury getaways to bus tours. Washington has a rule requiring bar-code tracking of every marijuana plant to ensure that only licensed, Washington-grown marijuana is sold in its stores. It has also created a niche for tech start-ups like Viridian Sciences, a software company aiming to help retailers prove the provenance of their product should a state inspector or customer ask.

But many have also discovered that selling marijuana, even without the specter of being arrested, carries high costs and no guarantee of success.

A heavily regulated recreational marijuana program in Washington drew more than 7,000 applications, but many of those would-be growers, processors and retailers have struggled from the start. They had to find financial capital that state inspectors would approve and lock in a legal business location. Then, they had to endure months of delays as overwhelmed state workers processed and analyzed an oversubscribed applicant list.

“I’m about fed up,” said Michael McDonald, a 57-year-old home-repair contractor, who has applied for two licenses to grow and process marijuana in Bellingham, in northwestern Washington.

Mr. McDonald said the deck was stacked in favor of richer corporate players. With banks still so leery of lending in the industry, he said, financing choices for smaller entrepreneurs like him are few.

“What’s happening is that the only people who are really going to get licenses are the ones who have somehow hidden their illegal money, or legitimized it, or it’s big business backing it, and that’s not how it was supposed to be,” Mr. McDonald said.

Aaron Varney, 38, who directs a nonprofit medical marijuana cooperative in Seattle, got a 24th-place slot in the state lottery for the 21 retail marijuana locations up for grabs in his city; three people ahead of him would have to wash out of the process for his number to come up. He wants the industry to succeed, he said, but cannot fully silence what he called the selfish voice inside that hopes to get in.