So, I am trying to understand what you did recommend. Reporting these illegal sales to responsible authorities? Which authorities would that be? Or maybe I am completely misunderstanding you, and you are not recommending any action on my part?

I'm pretty sure I recommended calling the police.

I had no idea the sale of fireworks was banned. As a foreigner, I don't feel comfortable with the idea of approaching vendors and explaining that what they are doing is illegal.

That isn't at all what I recommended. It's not your place to say anything to a vendor of a banned or controlled product.

No hay permisos para venta de pirotecnia: Reglamentos

Unfortunately, some folks have not gotten the memo regarding the use of pyrotechnics. In the area near Plaza Kioto they are already shooting off explosions at random hours of the day and night. Many stalls both in and behind the market are selling these devices. And once the pinata vendors open up along La Boquita, stalls there will be selling them as well. Ugh.

Since the sales of fireworks are banned, you can help by reporting them to the "responsible authorities". Unfortunately this is where jurisdictions come into play and it becomes obvious our laws were written by criminals for criminals, so we have to be insistent. Police actually don't have the authority to enforce a lot of laws without a formal request from the competent authority. The police will say it's the responsibility of Reglamentos, so you can remind them to please contact them, too. The key is to be courteous and respectful but insistent. That's how we get things done.

We're on the verge of big changes in Mexico, but it's going to take the participation of all of us to make it work.

Has this celebration already begun? I seem to recall the firecrackers (or small sticks of dynamite) going off at random times was part of the celebration, but it seems very early this year to begin.

No, Los Guadalupanos don’t start their morning caroling or they’re pilgrimages until December. The community is really trying to discourage the use of pryrotechnics including bottle rockets and firecrackers partly because the noise represents a health risk to animals and people.