I have some sympathy for your argument, but I think you are fundamentally misunderstanding the power dynamic between citizens and criminals.
Some of the petty thieves will think twice if they hear about other thieves getting beat up. Many of them will simply respond with violence.
Look at Latin American countries where thieves will shoot you dead for an iPhone.
The bicycle thieves are going to steal no matter what. They have to score their next hit. Better that they can do that armed only with an angle grinder rather than a pistol, too.
And if someone decides to turn a bicycle theft into a murder, well, the bicycle thief can usually "live off the land" much easier than you can. When you are used to living on the street and all you need is your next hit, it's much harder to catch you for murder, even if you can be identified.
In a fight where you have more to lose, are an order of magnitude more likely to be held accountable, and your opponent is irrational, effectively anonymous, and probably more practiced in violence than you, escalation seems unfavorable even if it leaves you with a shitty feeling.
Some of the petty thieves will think twice if they hear about other thieves getting beat up. Many of them will simply respond with violence.
Look at Latin American countries where thieves will shoot you dead for an iPhone.
The bicycle thieves are going to steal no matter what. They have to score their next hit. Better that they can do that armed only with an angle grinder rather than a pistol, too.
And if someone decides to turn a bicycle theft into a murder, well, the bicycle thief can usually "live off the land" much easier than you can. When you are used to living on the street and all you need is your next hit, it's much harder to catch you for murder, even if you can be identified.
In a fight where you have more to lose, are an order of magnitude more likely to be held accountable, and your opponent is irrational, effectively anonymous, and probably more practiced in violence than you, escalation seems unfavorable even if it leaves you with a shitty feeling.