For years I put all my non-bonus spend on my Costco Visa for 1% cash back because it simplified the tracking of my spending. Now I use an Amex Everyday which does earn a 20% bonus if I use it 20x in a month, so I'm "up to" 1.2% back on non-categorized spending. I should get the BPP to boost my 1.2% to 2%, or a 1.5% or 2% cash back card, but to answer 'why', I'm not too interested in establishing more credit and tracking another card