The banks do. Payment providers do. Advertisers do. There's plenty of reasons for a business to be low-key about providing accessories to break Federal laws.
I've never been to a dispensary in the US that takes credit cards, and MC and Visa specifically don't allow cannabis businesses.
https://www.cato.org/blog/cannabis-banking-clash-between-fed...
https://www.benzinga.com/markets/cannabis/21/12/24405152/its...
EDIT: Just read the company is issuing and processing their own 'credit cards'. I'm positive I've only used cards when buying from our dispensaries. Come to think of it, it's just debit cards but it's a card and it will buy weed if you want it to.
There are a number of workarounds (Colorado credit unions being a notable one), and fintechs like the ones described in the article you linked trying to provide card solutions, but they're still all locked out of the "normal" US banking system.
This is patently false. My close friend runs a $75M/yr wholesale distribution op out of Carpinteria, Ca, called Headwaters. He has multiple FDIC banking relationships for his business.
Credit cards are no-go. No airline miles from picking up psychoactives.