I seem to remember noticing this 5 years ago or so. While its true a VCR has more moving parts and is thus probably more expensive to produce, I think the main reason they went up in price is the demand dropped to a point where most companies flat out stopped making them. Which leaves a few companies left that can charge niche prices for them. It's like how when all the ram makers move to the new ram type the old kind skyrockets in price because the supply is dipping off.
Really though, when I looked they were like $75. While it was no deal it was hardly a complete ream job. I think they were even quality brand name 4 head units with stereo which make them basically the same price they were when I bought my junk unit in the 90s. I ended up just using my parents old unit...I record a show about once month maybe.
You know what's funny...everyone bitches about VHS, but at least when the tape was old and questionable it would usually play (albeit with reduced picture quality) unlike DVDs which often just lock up the player and skip over entire sections if you're lucky. And when you wanted to skip the previews, your VHS never displayed a large international "no" symbol and forced you to watch a copyright warning display...in 3 different languages! DVDs blew VHS away at first, but it seems like they're really busting their ass to make it the worst experience possible these days.