We're not talking about when they've grown up though, you made the comparison to kicking a naughty child misbehaving on the bus to someone kicking a dog running up to their children in a threatening manner.
It's very simple.
Threat posed to you by a naughty child misbehaving on the bus (or anywhere else) - so small as to be insignificant (unless you're in the US where they seem to periodically get hold of loaded guns
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)
Threat posed to a child by a dog jumping up and snapping at it's face - potentially life threatening.
There's no real comparison.
Whilst I know that in 99.99%+ cases it will be fine and the dog is most likely just overexcited and coming to say hello, I'm just not willing to take the risk with my kids that this time is that 1/10,000 case.
If you are unwilling/unable to control your dog, then as far as I'm concerned, you lose all right to take offence when someone else is forced to.
The fact you've acknowledged your own argument is absurd, but still continue to labour the point just proves that you're more interested in being a **** than actually discussing a valid point in good faith, so I'll leave you to it.