Presumably, Kent paid off the Mugger so as to protect his secret- viz. that he is an alien from the Planet Krypton and thus has no 'Human Rights'. If the Mugger knew Kent was Superman, his crime- if it is a crime- is that of blackmail, not of demanding money with menaces. If he didn't know this, then he may still not be guilty of anything by reason of impossible attempt.
Suppose Superman's secret identity was that of a Sikh shopkeeper rather than a mild mannered reporter. Then, in order to remain in character, he would have to get shot or knifed by the mugger and then chase the ruffian down, while bleeding profusely, before capturing him and handing him over to the police. To do any less, would raise eyebrows at the local Gurudwara and incur a hukumnama against the practice of wearing kaccha over, rather than under, one's trousers.
Sikh Superman proudly wearing kaccha over his trousers
This gedanken suggests that with unrestricted domain, coercion isn't something which can have a purely transactional definition. It arises in a cultural context. The attempt to distinguish a concept of coercion, abstracting away from cultural facticity, is doomed.
Take this example, from Japa Pallikkathayil-
Essentially, for this analysis not to be empty, there have to be pre-existing cultural norms and practices such that the crime of Mugging isn't inchoate. However, it is of the essence of cultural norms that they surpass the bilateral, or otherwise transactional, and, indeed, constrain even transcendence.
Like Superman's kaccha constraining his testicles.
Sikh Superman still wearing kacha over his trousers but starting to feel a bit of prat.