Your understanding of life is so weird!
The difference is this...
Gender Reveal:
A couple of people without malice and no intention of setting the fire were having fun trying to reveal the gender of their baby to themselves and their families.
Stupid? Yes. Malicious? No. Intent? Reveal the gender of their baby.
Rioters:
A mob of people full of malice and every intention of setting the fires having and no guilt about killing people in those fires.
Stupid? Yes. Malicious? Yes. Intent? Destroy, burn, violence, etc..
You are pretty dense if you don't understand the difference between these 2 scenarios. I am appalled and shocked you would equate and conflate the two. What kind of bizarre twilight world are you living in?