Yeah - this is kind of impractical in today's lighting environment. It might have "meant" something back in the day when the standards were single bulb MH fixtures where the lamps at least had a stated temperature and everyone knew what to expect from a radium bulb for instance.
I have found our local fish (coral) stores to be pretty accommodating about adjusting parameters temporarily in the shop to try and simulate full spectrum but there is a limit to what they can realistically do given all the variables.
All that said, the post photo saturation manipulation is kind of irritating and one reason I have stayed away from online sales/auctions except from trusted (local) sources. But then again... I am kind of risk averse in that regard.