There has to be a balance between artificially low caps and users being allowed unconditional unlimited access. Neither really works out well.
I don't understand why nobody has done a "nights and weekends" thing for data. It seemed to work well enough for voice calls back in the days when capacity for them was actually an issue. Why should AT&T or Verizon care if you are pegging the tower at 4am when hardly anybody else is using it?
This seems like something they could give away that would cost them next to nothing and earn a little bit of goodwill in response.