Can racks cause damage to a bike? Reading this question about the best way to lift a bike on to a pictured rack, it struck me that I'd be less worried about how to lift the bike than the potential for damage by hanging the bike from its front wheel's rim. 

Many racks involve putting the rim into a trough or groove, or something like this attached to a wall: 

Surely the danger from being struck from the side and bending the rim is quite large? For this reason I try to avoid any rack that I have to put my bike in rather than against or on. 

While the concensus seems to be that public rack owners might not be liable for theft, might they be liable for contributory negligence if a bike is damaged directly as a design flaw in the rack?
I am not a lawyer, but it looks to me that it would be a big no. It is your decision to put it in the rack. 

And in any case, they are actually pretty good - they are the most common type and I have never had one cause any damage in 35 years.