The difference is one set of protestors support US/Israel intervention for regime change.

The other group of protestors are protesting against this. There is a segment within this group that are ardently pro-Regime. The other segment (which I think is the majority of the group, and Iran, but I have no evidence and so this is purely anecdotal based on my various discussions with Iranians) is that they do want regime change, but not from any outside influence - they would ideally like an organic democratic process that Iranian citizens control.