Welcome to POTN!
Hasn't been a problem so far but I rarely get to the big city.
I have a camo tatt00 sleeve slid over mine for photographing wildlife from the kayak. It is long enough to cover the lens fully extended. It bunches up nicely when not extended. It really works well so it is pretty much on the lens full time.
You can buy them on-line really cheap. Here is a link from Googling "camo tatt00 sleeve." http://dx.com …tockings-camouflage-37449
Or you can get an old long sleeve t-shirt of the preferred color, cut off the sleeve and hem it.