Not to mention the taxes, depending on where you live. When I actually went to register my side gig wedding photography business it was the most confusing mess I've ever had to slog through.
It's not clear, at all, what licenses you need because of the nature of the business. There's state, then there's also local/city licenses, and it's not clear on if you need one for every city you photograph at, or just one for the city you reside in (your business address). Some cities require it some don't.
Then the taxes here are also just as confusing. Different rates depending on the business activity. Session fee revenue is taxed differently than digital photo sales revenue, etc. Then sometimes the service itself is subject to sales tax, sometimes not, depending on how (and where) you deliver the photos matters too.
You can't be on the legal up and up without hiring an accountant and maybe an attorney to go through the process with you, which is definitely not something I wanted to do for a side gig.
It should not be this convoluted or difficult to legally open a business, especially under a certain amount of revenue per year. I'm not making millions here, we're talking less than 100k/year in gross revenue.
There's a reason most photographers here just....don't bother to register with the dept of revenue. Most don't get caught anyway so a lot of times its worth the risk to just..not pay the taxes.
None of that bureaucracy should exist for businesses under a certain size/under a certain revenue.