Hello chaps, need some advice.

My car is housed in an open sided wooden structure. This keeps the rain off it but not the dust, pollen and the like. In the past I haven't had a cover on it but quite recently a visiting friend suggested I do so. I am of two minds because while it would keep the grime off my p&j, I have been told covers scratch the paint and are actually damage the paint.

I would relish hearing your opinions.