The connectors used on PC cases - for the front panel, USB, TRS sockets for audio etc.. - tend to be of pretty low quality regardless of the cost of the case. The connectors used on motherboards however, are higher quality as they are part of the motherboard itself and because few repair them, often can determine the life of the mobo itself. (so it pays to not go cheap).
Also, USB connectors on the motherboard are mounted on the board itself, soldered for mechanical strength and tend to be rather rigid. OTOH... connectors in the PC case are mounting on fairly cheap SRBP PCB material, losely held in the case. This means they move a lot more, further increasing the strain on the already cheap connectors.
I have seen cases costing >£300 with the same cheap USB sockets and terrible wiring, unshielded cables to female headers, so these extra sockets/connections are pretty much an after-thought.
I also replaced the sockets in my case, with a new board (FR4 home etched, as there's no actual electronics on board) and they still tend to break, so I've opted for what you suggested, a sacrificial USB hub. If you're lucky enough to find a metal case one, bolting this to your PC case ensures it doesn't flap about in the wind. I have yet to find strengthened sockets, but standard A sockets, properly mounted on proper PCB that itself is properly mounted tends to be pretty damn rigid. It won't survive a 200lb gorilla, but that is why its best to make it easier to replace.
A powered hub can also help with power issues on the USB lines, as many powered hubs these days are pretty slack on their current limit (USB 2.0 rated for >1A) and should add another layer of protection between the sockets and your PC.