1. Listening to music on a speaker.
This can disturb focus of many golfers practicing at the range. Using headphones can help avoid this.
2. Talking on cell phones.
Talking loudly on cell phones about private matter is something golfers could care less about.
3. Leaving their practice spots.
At an busy driving range, it's a basic etiquette to finish up your practice without constantly leaving your spot idle.
Of course people are free to smoke at a smoking allowed areas but at a public driving range where no smoking is allowed, it's very inconsiderate of other golfers to blow smoke.
5. Setting up right behind other practicing golfers.
This is very rude and can pressure golfers. It is also dangerous to set up and stand behind golfers. Let's give golfers their space.