As pointed out above, Chrome no longer does this... but adding wear is a natural consequence of any hard drive scanning process. SSDs are rated for a certain number of read/write cycles, and every time a block is read, it adds wear.

Even spinning rust wears out eventually. Not knowing any details about how often Chrome did this, it is hard to say just how significant this wear would be compared to other normal uses of the media. But it is clear that wear would occur to some degree.