The government could ban drugs. What then? Guess you won't find them anymore. Definitely no illegal drugs in Argentina.
Breaking the law is a requirement for survival there. Basically all the big employers have to do it, no one seriously pays all their taxes as they can be non-hyperbolically over 100%.
Ok, so then why not just use USD? After all, breaking the law is a requirement for survival, so why concern yourself about breaking one more law (using USD)?
Well you can use USD representation like tether or GUSD.
You may want to acquaint yourself with taxation in Argentina. There is a tax just to put money in your bank account. To deposit your money. I recall it being small but above 1% but I can't remember the amount off hand (Edit: 0.6% for business account transaction) [0]. I'm not sure if there's any mandatory exchanging to pesos when depositing, but that may be the case. I'm not Argentinian. If that is the case it makes things way worse.
You have to bring the USD into the country somehow. I think crypto is a convenient way to do that which avoids capital controls imposed when entering the banking system. I guess you can bring in gobs of cash on your person and that works as well, although there's the tradeoff of being robbed or whatever. But bringing in USD sounds OK too for some people and it is very easy to smuggle in border with Paraguay as there is basically no control at the border. For some it may be a personal preference.
Breaking the law is a requirement for survival there. Basically all the big employers have to do it, no one seriously pays all their taxes as they can be non-hyperbolically over 100%.