Being straightedge is not a trend or fad however some people follow it, or pretend to, to seem cool. (see: scene kid, emo). Being straightedge doesn't mean a person can't have fun or is too scared to do drugs, it just means they don't have to do that to have a good time.
Some people who are straightedge have already experienced the drink-and-drugs way of life and have decided it wasn't for them, or there was no need for it, one famous example being Ian Watkins of Lostprophets.
As it is a lifestyle and not a set of rules, many people have their own form of it e.g. some straightedgers are vegan/vegatarian, don't drink coffee or refuse medicinal drugs; these are not principles every straightedge person follows though.
Straightedge has nothing to do with religion. Although the idea of refraining from casual sex, drugs and alcohol is one seen in many religions, you don't have to be religious to be sXe.
Many people are straightedge without realising it - they don't do it to be righteous or follow a trend, they just are. Some people wear shirts with slogans like "poison free" but these are the type who are often very smug about their lifestyle and want to show off or force it onto others. People like these, and the emo/scene posers, are the ones who give being straightedge a bad name.
Guy: Hey, you want a beer?
sXe Girl: No, thanks, I'm straightedge
Guy: Oh sure, no probs
Poser sXe person scenario:
Guy: You want a beer?
Poser-emo-scene girl: Oh fuck yeah! Ignore the cross on my hand, that was just for show for my millions of myspace photos. Wanna go have illicit sex later?
Extreme sXe person, known as being hardline:
Guy: You want a beer?
Hardline girl: Oh my fucking god, what the fuck? Why the hell are you drinking?
Guy: Woah, chill out
Girl: No I won't! (spends next 3 hours forcing her beliefs onto him (including veganism and refusing medicinal drugs, may get violent if he refuses to listen)
Final type of sXe person- the smug one.
Smug sXe girl: I'm straightedge! I don't drink, take drugs or have casual sex.. no I know you didn't offer, but I obviously felt the need to tell you because I'm so smug about it.
The majority of people are the first example (and they might not even say they are straightedge) so don't lump all people who are sXe together. The real straightedge people will be the ones who are still sticking it out and staying clean in 20 years time, and who disagree with hardline people.
3)no promiscuous sex
4) Yes, we do have fun
Times as they are, there are now three kinds of sXe'rs.
1. Those who understand what it means. People who value clarity and wish to avoid altered states of perception, poisoning the body, or unsettling the mind. No drugs, some even avoid medicinal drugs as these can alter state of mind. No drinking to excess, as this can alter the mind and poison the body. No promiscuous sex, you got me on this one. These people are, 99% of the time, decent people who see their choices for what they are, choices, nothing more, nothing less.
2. Insecure gits. People who wish to place themselves on a self appointedly superior moral platform, then proceed to brag about how much better they are than everyone else. No drugs. No drink. No Promiscuous sex. No meat. No/very few friends, as few other than those who share their views can stand to be around them for more than ten minutes without driving a lit candle, wick first, into their eye, and injecting them with lighter fluid through the ear.
3. Hardliners. All the stupidity of number two, with knuckledusters. No drugs. No drink. No promiscuous sex. No meat 9 times out of ten. All the clarity with none of the intelligence.
2. Stop poisoning my air you arrogant ignorant smokers!