To put in terms that might fit more with your universe, thank about if all humans were at least a little magic but only wizards had a lot of magic and a way to control it. So for normies, all= their negative emotions sends their magic swirling around all over the place. Locations like hospitals, schools, grave yards et cetera in particular are likely to have a cloud of it all the time.

That's basically what we call 'curse energy' and when you have a lot of curse energy, curses are created. Monsters that run around doing everything from being annoying to causing massacres. Sorcerers don't create curses because we can stop our curse energy from getting away from ourselves, instead we use it to do our own brand of 'magic'.