...or sweat in the gym

Just got home from accompanying a friend shopping for supplements. Encountered a scenario which I find rather disturbing, you tell me if it's just me yeah?

So, as we were browsing around there were these 3 college kids (I think) grabbing a tub each of NO Xplode. 2 were skinny, the third was very overweight and all 3 didn't look like they've ever been in a gym. Now not to discriminate but with my curiosity piqued, I tried to strike up a conversation.

Me : You guys planning to hit the heavy weights huh?
Them : No lah, we don't go to gym wan. Later become like all the muscle guy haha
Me : *bites tongue*
Them : This one good for study! Take one time really can concentrate. Some more during exam time add extra a bit...really can feel the effect
Me : ...... *shocked*
Them : *runs off*

Is it just me or is there something seriously wrong with this whole scenario?

actually i did tried once pre workout before study.
its like multiple shots of coffee. lots of concentrations/focus

i works well for me but i dont think thats a good idea...
maybe doctors here can explain weather its good or bad.

i tried it just once thou.. supps are expensive.
i rather have 2-3 cups of coffee to study lol.