Not many perch in my area but I have seen the same thing with other panfish. The ones I have caught have been really timip. Almost feels like you have to piss them off enough to bite.
I had the same issue with perch most of last winter. Tried less traveled lakes with same result. Lots and lots of lookers but few takers. I haven't been out this year yet to I can't comment on that, but last winter was frustrating for me!!
Nothing brings out stupid people like a big buck or a hot perch bite. As many people as I saw on some of the perch lakes last year, it would not surprise me that some got cleaned out pretty good.