This video will make your day: Sikh immigrant shop owners teach thief a painful lesson

[Absentee Voting Ghost of Ruin]

How many of you think he should be allowed to walk free because of his beating?

The armed robber was not beaten, he was subdued. And even if the employees committed some crime in subduing him (IANAL, but I can't see anything I would consider a crime) then they should be facing charges of their own. The perpetrator is still an armed robber and needs to be prosecuted on that basis.

[Absentee Voting Ghost of Ruin]

How many of you think he should be allowed to walk free because of his beating?

The armed robber was not beaten, he was subdued. And even if the employees committed some crime in subduing him (IANAL, but I can't see anything I would consider a crime) then they should be facing charges of their own. The perpetrator is still an armed robber and needs to be prosecuted on that basis.

People on twitter are demanding the employees be arrested and the robber released

According to the guy who owns and operates the-website-formerly-known-as-twitter it's full of bots. I certainly wouldn't take it too seriously.  I mean, "people on Twitter are demanding" is semantically equivalent to "random posters on the internet are demanding" and no one should take that seriously.