My guess is that 99.9% of the general population has no comprehention of hormone levels and what they do for you, while AAS users would be much more educated and likely to ask their doc's the right questions.
If all you do is sit at a desk all day and file paper, come home, drink a few beers and watch TV then how would you ever know your test levels are sub-par? You wouldn't, low sex drive would probably be blamed on something else. But for older guys that have been lifting for years, they'd know if it suddenly started to drop off - less motivation, lowered sex drive, stopped gaining muscle at the same rate, gaining fat, less strength etc. They'd see the signs in the gym and else where and know the cause.
My theory anyway
