Plus, a warning for mines. And of course...
"Just when should I activate my Shield?"
"Energy Drain, huh? Time for a Deflector!"

And then there's the factor of people coming from Other WipEout games; Wip3out and 2048 are the only games in the series (to the best of my knowledge) that warn you about which weapon you just picked up, rather than which weapons are being used against you... and games like 2097 and WipEout Pure/Pulse/HD are the ones that brought the most players to the series... and as such, most people playing BallisticNG are probably more familiar with the proper warning system. (It is worth noting though, that while Wip3out had a generic "Warning!", 2048 didn't have a warning system period)