From what they wrote, it looks like they probably said something along the lines of "Hey, here's a ___location where they don't care if you are in an at risk group, you can just show up and get your vaccine." Considering it was back in March, people probably found it wrong to be advertising that to a bunch of people who are probably healthy and well-off, instead of people who actually needed the vaccine.

I'm not going to make any judgements about it though, considering I don't know anything about how things were in California. In Maryland they had county level registrations that went through tiers of at risk groups, plus state-wide vaccination sites that were open to anyone, so I ended up getting my vaccination a few weeks before I would have if I'd waited for "my turn" with the county vaccination program.