We've never had a single argument over money. In fact we agreed a long-time ago to pay certain bills as our own responsibility. We buy groceries as we need them for the household and so on. We each pay for our own car repairs, gas, and car registrations.
When either of us treats the other for a special dinner or event it really feels like we are treating one another!
On the other hand if all our money was tied up in joint accounts I believe there would be opportunities to be resentful over how one person may be spending money. There might even be "surprises" when one person goes to the ATM and or attempts to make a purchase and learns there isn't enough money to cover a purchase.
There is no "right" or "wrong" way for a couple to handle their finances. Some people feel that it's best to joint everything.
Whatever works for you!