If a fault happens in any of the circuit (cut wire, broken lamp, racoon chewing a wire), the Series circuit will disconnect the lamps from the battery. All the lamps will turn off. If highly sophisticated appliances are involved, a sudden current cut will be detrimental.
The Parallel circuit will have less chances of shutting down all its electrical load (lamp, buzzer, computers). Cut a branch off, the other branches will still receive electrical current.
Troubleshooting will be much easier too. Just find the spot where the lights don't work and inspect that area. Series circuit on the other hand is difficult. In some cases, you might have to inspect the whole circuit.
Imagine trying to inspect a Series wiring in a house instead of a Parallel wiring.
Neither or both, you decide.
The question is rather arbitrary and does not have a good scientific answer unless you can define "economically better." Even then, it's not really a scientific question.
Power distribution systems, appliances, and electronic devices use many types of circuits involving both parallel and series components.
A two slice toaster may be a series circuit while a four slice toaster has two parallel circuits. Is the four slice toaster economically better because it can cook twice as much toast? Or is the two slice toaster better because it costs much less?
The question makes no sense. We need both types of circuits. The best choice depends on delivering the optimal current to the components so that they can operate properly and efficiently. The best choice for Christmas lights may be a poor choice for television sets.