I used to use a spray bottle long ago and quickly learned that it doesn't do anything. If it stops the fire, it's only for 2 minutes until more drippings from the meat come down. The trick is to get your temperature right and clean your BBQ regularly. If there's lots of cruds below and the drippings pool in spots, it will ignite. Don't just keep your grill clean, but clean everything below as well once in a while.
That's where a lot of people don't realize where money goes for a good grill. I could take apart my old Broil King Sovereign, clean it and put it back together in 30 mins. It was a pricey grill, but everything could be taken apart and replaced it need be. Many cheap grills don't give you that flexibility. Everything is screwed on and the screws will fuse with the heat.