Lol as if drinking Soda every now and then is going to matter. Hell even MMA fighters drink Soda when they are not training. Its only bad if you drink it constantly. Someone who stays active and maybe has a soda once or twice a week isnt going to feel any negative side effects from it.
Most things are bad when overdone.
Some things are worse than others though. You overdo something like, say, cabbage, the worst you're gonna have is a bloated stomach and a bit of gas. You overdo soda and you're gonna be a diabetic with a heart attack. You overdo prescription meds and you're dead within minutes.
It's also about how much is "overdoing" ... again for something like cabbage you can literally eat a full cabbage for every meal for a year and not have any problems, in fact it's probably healthy. You drink a full bottle of coke for every meal, you're practically guaranteed to be a tub of lard and halfway to diabetes by the year end. And it's much easier and tempting to drink a full bottle of coke than eat a full cabbage, it just fills you up quicker.
I do agree with your general attitude of moderation though, I also sometimes have a glass every few months or so and it's not like I never have ever have a rum and coke etc. It's just that I'd usually prefer something better than that crap.