Does the city water dept change your water pressure?

I have no leaks in my house, and I usually only use about 70 gallons per day on the average. Once a week, I will do two large laundry loads which runs to abut 150 for the day. However, recently I have noticed that my meter shows I'm using 100 gallons per day several days in a row when I'm using about the same as I do on a daily basis. Again, I have checked for leaks in my house as well as at the water meter. No signs. So, does this leave water pressure? If so, why would the city water dept change the water pressure? Can they control the water pressure for each individual house? I can't understand what the problem is.