We're talking wild grass here, not lawn, so if I let it grow to length it can get pretty tall. Last year we had record rain and in the front it got to almost 5ft tall!! I don't think rooting is an issue for this grass
Yes, it is extremely dry in the summer.
If they catch them, they get to pay big fines as well as the cost to fight the fire. A small fire will easily be in the tens of thousands to fight.
This is what my yard looks like, as well as the surrounding million miles or so, so fire would not be good:
My property line ends just before the second large oak in the center.