> My understanding was that the crime in those areas was so astronomically high that nothing even resembling IT infrastructure could exist, as it would immediately be confiscated by the cartels operating there.

Your understanding appears to be empirically wrong. The thing about poverty is that you learn to depend on those around you, and gang membership aligns by neighborhood or even specific blocks.

Outsiders may be fair game, but locals have built relationships within the community over years. The armed gang member may feel some loyalty to the organization that let him play games when he was 10, and he has a cousin/friend on the eSports team. There are very few secrets in such close-knit communities you cannot secretly steal and fence the equipment without someone knowing - outsiders can't either because there is always someone keeping vigilance (hence the guns).