Caffeine is not a drug. Even alcohol is not a drug (unless you are an alcoholic).
Of course caffeine and alcohol are drugs! Just because they're not prohibited, it doesn't mean they're not "drugs".
We wouldn't use them for the purposes which we use them if they weren't drugs!
If someone can't leave the house in the morning without first having a coffee or beer or cigarette or bong, then they're a drug addict 
If your mother knew about your morning beers or bongs, she'd slap you, but regarding a morning coffee, she'd ask you to make her one too. Why? Because in typical dosages it's not harmful.
Someone who enjoys a coffee every morning (regardless of whether they *have* to, due to dependency, or not) and a glass of wine every evening will live just as long as anyone else. They may even live longer than someone who abstains from these drugs!
It doesn't mean they're not drugs, just that we're socially acceptable of appropriate public use of these drugs, for either recreational use, or performance enhancement.
This very casual conversation about how much people drink coffee or what experiences they had with some other caffeinated product is somewhat confusing. In most cultures drugs are a sign of weakness.
Don't be so smug and sure that you're better than these "weak drug users". Certain kinds of drug use is normal in most cultures, I bet you're consuming many more than you're aware of.
Abusing (not just using) any substance is bad:
- someone who has to be drunk all the time will die of organ failure eventually.
- someone who has to smoke daily will quite likely get cancer or organ failure eventually.
- someone who has to drink extremely high (overdose) levels of caffeine all day long will likely experience heart failure.
- someone who eats deep fried food for every meal will become obese and also experience organ failure
People who are abusing a substance to the point of self-harm are not weak, they either ignorant (people who don't realize energy drinks have dangerous dosages in them), or suffering a mental illness and need your help.
Alcoholism is obvious self-harm, that will eventually lead to death, but drinking a strong coffee in the morning will not kill you.
In most cultures, use of certain recreational drugs is seen as entirely normal, and people who avoid such traditions are seen as suspicious.
In most countries, this includes either beer, wine or spirits, teas and coffees, and smoking products. In some places, it may even be socially acceptable to smoke opium in moderation, or other practices that fall under a prohibition elsewhere.
I know a lot of places I could go where in a social situation I'd automatically be given a beer, and if I declined the offer by saying "sorry, I don't drink", I'd receive more than one confused look.
Simply reapplying the same drug repeatedly will have diminishing returns, and I doubt caffeine can be seen as an exception.
It doesn't just wake you up, it grabs you by the collar and jerks you up out of your chair shaking you with both fists. A few days of this and I think anyone's going to feel really beat up and tired, maybe another hit of the stuff will keep them awake.
Caffeine tolerance can increase with use, but quickly returns to normal with abstinence. However, you have to have quite high usage levels in order to increase your tolerance. Having one coffee each morning, or half a dozen cups of tea a day is not likely to build you up a strong tolerance.
I don't know what kind of caffeine you've been trying, but I've never been jerked up and shaked around by my coffee. You might want to try a nice mild cup of tea
