I have heard the story, it does raise interesting points. In St Louis there is a requirement for a bicycle tag, a sticker I believe. The arrestees were members of a group that is known to affiliate with the Seattle rioter types. I believe the cops were trying to keep them from what was feared to be (but hasn't materialized) the downtown riots.
So, they were in violation of at least an ordinance level law. I do not know how they were riding their bikes. (I.E. taking up the whole road, interferring with traffic, running stop signs etc.) And they were known to associate with criminal groups.
Now compare this to slinging you AR over your shoulder (but not brandishing it at folk) and walking around downtown. You can bet your last dollar you will be stopped and told to get the hell out of there immediately. That is if you are lucky, I would bet more on confiscation and detainment. Of course your actions would be perfectly legal, open carry is allowed.
Would anyone out there be upset at tossing a gun toting loon in the big house even if what they did was perfectly legal?
A bit rambling here but I hope it causes a little bit of contemplation. Personally, since they were in violation of the law (regardless of the stupidity level of such) they should have to answer for their actions. Locking them up is harsh I think but I do believe maybe a fine would be in order. Just like it would be for everyone else.