The Panthers did free before school breakfast and after school babysitting and all sorts of actual community building like that. The PSL does protests and craft events and that's it. I guess providing consistent services is an order of magnitude more difficult than organizing marches but it just doesn't seem like the marches are getting us anywhere.
Don't worry about them. Start something yourself if you need to. In my experience, there's a lot of people out there that are just looking for opportunities to get involved. If you build it, they will come kind of thing. Please resist the urge to bring sectarian frictions into your organizing though. Focus on broader aims.