Lots of things are on the DEA list. I'm pretty sure the DEA List is not about using the stuff at all, but is about regulating the people who sell it, particularly in large quantities.

Maybe a normal person wouldn't want to, say, synthesize known components of flower nectar and put them outside in bowls of sugar water to see if they attract more bees than plain sugar, but a teacher might want to do that sort of thing. Might a hobbyist? I don't know.

Threads like this make me really nervous - I feel like my fellow chemists would condemn me for having bottles of things from the hardware store. Of course I'm more of an ex-chemist right now, but I still love the art of chemistry. Ordering is a real bureaucratic hassle and budgets are limited, so I often use commercial products for lab work. Sodium carbonate is pretty much sodium carbonate whether it comes from Fisher or a pool supply store. I prefer actual ACS grade sulfuric acid for when the kids are making esters, but if I'm just cleaning the glassware after the annual preps of iron ochre pigments, drain cleaner grade is just fine. And so on. I do have fond memories of working in well-equipped R1 university labs, where nobody would dream of using such a 'reagant', but that was then and this is now.

Yes, I do know of commercial products with a significant amount of benzaldehyde. Not sure I should say, though. I still maintain that someone who wanted to make meth on a scale of a few grams would have a much easier time starting with Sudafed. Those guys are not real chemists, they don't have the heart for multistep procedures.