I believe there may be challenges for service industry workers, such as waiters, room cleaners, and taxi drivers, to easily exchange small USD bills for useful pesos. Most advice suggests bringing larger denominations like $100 bills for better exchange rates. However, this presents a dilemma when it comes to tipping, especially if you're considering giving a $5-10 tip. It's unlikely that service professionals would receive a better-than-bank-rate price for these smaller bills, and the Argentine government's restrictions on access to USD may complicate matters at banks.
For example, when tipping the building doorman (encargado), who likely prefers pesos, offering a more substantial token of appreciation, perhaps equivalent to USD$100, might be more convenient for both parties.
While some touristic and expensive restaurants may handle USD more readily, it's not always the case in everyday situations. To address this, it might be beneficial to ask the person receiving the gratuity about their preference. Having open communication about currency choices could lead to a smoother and more appreciated exchange for both the giver and the recipient.