Just because governments and mafias share that one characteristic doesn't mean they are the same. There is a whole lot more that governments provide to a society than collecting taxes.
Businesses also collect revenue, and if you don't pay them, harassment will also ensue, which you'd know if you've ever forgotten a payment and had a file sent to a collection agency, and ultimately to a civil court which is paid for by ... government. But that doesn't mean businesses are like mafias.
What distinguishes organized crime syndicates from governments and businesses is everything about them apart from "pay or be harassed" part, including but not limited to: the family-based structure and power inheritance model, the use of localized violence as coercion to payment (vs in exchange for services provided), and the lack of any transparent system of justice. Some governments (i.e. Saudi, North Korea) undoubtedly have more of those characteristics, but that doesn't mean that most governments are equivalent to organized crime syndicates.