Their payrolls and organizations became too big for them to maintain with strictly the activities and income from dope. In the 90's much of the common youth saw the false glamor of the DTO's and aspired to have the material things that these groups have. Also, the acceptance and "out of the shadows" of these groups made them much more visible to Mexican society and thus their activities were much more accepted.
As these groups grew the fight for wealth and prestige was on and at that point they were not going to go back into the shadows again. Politicans and many of the ruling class were compromised and the younger of these classes don't know how to generate the wealth of their predecessors, but are accustomed to the frills of wealth. Thus they are given to being complicit to the activities of the now much more sinister criminal groups.
With the incorporation of so many people to them these groups grew to absorb all kinds of nasty and bad people that otherwise would have just been mere criminals without the advent of guns and means to corrupt and subvert. The income from drugs makes comprimising society in general possible. All bad things.
Greed caused the cartel wars, the wars caused paranoia on cartel leaders, paranoia made them create bigger armies, bigger armies cost more money so they let their gunmen venture into other criminal activities to help absorb some of the payroll.
IDK about CJNG, but CDS lieutenants in Baja also allow their lower rank members to "get a little extra on the side", sure, they are nowhere near as obvious as Zetas, but they do make extortions and kidnap people. I could only guess CJNG is the same.
It is the cartel v. cartel wars which brings them out of the "shadows." If every cartel respected each other's territories there'd be no cartel wars. Theses Wars make them visible to everyone, obviously a shootout will cause attention and innocents are killed as byproduct of these wars.
Also just like what Tijuano said, "Greed." Once people get a taste of money/wealth/power they usually want more and more and more... So once they get a taste they will do anything to get more money, just like a drug addict.
And now with the introduction of social media, narcos love to show off what they have and the lifestyle they have obtained.
I think it is the mainly the cartel wars which bring attention to themselves. Regardless of social media, the wars cause so much destruction and attention that the gov has no other option than to intervene. If the cartels stuck to trafficking only and stayed out of the limelight, and repected each others territory, I think things could return to ways things used to be. However, only if kidnapping and extortion stopped, but I dont know if thats possible.
We all look at Zetas as being the first to kidnap and extort money from the innocent people but if I recall it was CAF who began doing this when all the big bosses got arrested. I recall the exodus from business owners inTJ to San Diego because of this. As far as CDS, anyone gets caught doing this in Sinaloa they are dealt with immediately. Nor Mayo or Chapo allowed that shit to go on on their home turf. That's not to say it didn't happen but it was either to silence someone or someone went rogue.
CJNG do all this crap too, but coming from someone who has lived in Jalisco and has a lot of family in Guadalajara and Los Altos area. I can tell you that all the plazas that where once controlled by Los Zetas and are now CJNG, are a lot more calm now than when the Zetas where around. I am not saying that these crimes have completely stopped in these areas, but they have significantly gone down. An example of this would be in my parents hometown, a few years ago when their where zetas around you would never see a soul on the town's plaza pass 11pm. Now your out at mid night and there are plenty of people still out. People there drive around empty highways with a lot less fear than 3 or 5 years ago. Same thing with my family in Guadalajara, they own hardware stores and have told me that they would get extort a few years back, but have not had any of those problems in the past 3 years. But yet again, it could depend on who the local or regional plaza boss is who may or may not allow things like that happen.
But if I have to make a little list rating cartels or drug gangs, from most to least decent it would be:
1. Cartel de Sinaloa
4. Juarez/La Linea
6. Cartel del Golfo
7. Caballeros Templarios
8. Regional independent drug gangs like La Barredora, Los Rojos, CIDA, Cartel de la Sierra, La Familia Michoacana and specially Guerreros Unidos.
9. Los Zetas are on a league of their own.
The Alex Jones in me wants to say the reason for so much crime was started when Calderon or his advisors, along with American "intellectuals" decided on the "one cartel above all" strategy.
I would rather believe in something more "realistic". Money makes you weak. Yes, I know it sounds strange. Considering, money can buy bodyguards and even loads of poor men ready to die just to put food on the table. If only those capos would have had enough "huevos" to confront each other, thousands of lives could have been spared.
I know some things are better forgotten, but who is going to forget all the execution videos BB readers witnessed the past, 6 or so, years... ??? Always calling each other out, yet we've read they somehow managed to arrange meetings and even "truces", in the past.
Decent cartels will exist when dumbasses stop loving "the patron" more than they love themselves. Meaning that will never happen. Money turns females into something I would rather not say, sometimes. It can also turn men into frontpage news just so the patron can sleep good at night.