scrimp on (something)
To choose to consume or spend on something very sparingly or frugally as a way of conserving one's money or resources. I got so used to scrimping on food when I was broke so that I could afford my rent. Now that I have a decent salary, it's hard not to have the same mentality. We cut corners where we had to so that we could afford the wedding we wanted, but we made sure not to scrimp on a good photographer!
scrimp on something
to try to economize on the use of something; to fail to use enough of something. Please don't scrimp on the quality of the food. There is enough money. You don't have to scrimp on anything.
To consume something sparingly in order to conserve it, or be frugal when buying something in order to save money: When my salary was cut, I had to scrimp on food in order to pay my rent.