I use cash for everyday spend and only pull out CC's for MSing. Keep separate checking accounts for MS and regular spend.
I don't know about you but my everyday spending likely makes up ~1% of my points accruals. 99% comes from MSing.
Much of everyday spending is not impulse spending and should be done with a credit card. Utilities, for example. Large purchases that you're planning and researching, like moko said, also should go on a cc.
I understand that groceries, lunch and 'shopping on the avenue' may be where many will overspend because it's plastic not cash. But cc's shouldn't be used only for MS.