Well Basics, argument number 1 is also a little different though. Sure McDonalds and Coke are bad for you, but when you eat and drink them, you're not hurting anybody. But with drugs, they can prove very harmful to other people, such as second-hand smoke, drunk driving and the altered mentality.
Some of these drugs are made illegal, because although you may use them responsibly, unfortunately, a huge chunk of people don't seem to get it that they have to be used in moderation, and therefore start to use them so much that it harms other people too. If everyone was using them responsibly, then sure, maybe there would be more favour for legalization, but as it stands, the chunk of people who don't feel like using drugs responsibly are the reason that a lot of drugs are legal.
If any drugs were to actually be made legal though, weed would be the only one, since the other illegal ones seem a lot more dangerous.