Probably that fence is someone’s private property.
And that someone doesn’t want bikes chained to it.
If it is his/hers property, he/she has a right to decide how it should be used.
Not entirely sure what an ”angry font” is.
This person may well have tried a milder approach earlier, only to find that it didn’t work.
And, slightly naive, or oblivious to human nature, decided to try again with a bit more aggression.
Which seemingly didn’t work either.
So now you have at least two adults being stupid in public.
Stupid #1 for taking the time to deliberately annoy someone with a rightful interest in the matter - the person chaining up the abandoned bikes.
Stupid #2 - the fence owner - for letting the actions of one or a few persons decide his/hers opinion about all cyclists. And acting in a manner most likely to annoy a larger group of people who until then didn’t have a stake in the matter.
It’s not like the world has any shortage of people acting stupid,