I'm the IT critter for a town in Mass and I manage the online stuff, including mapping. It's possible that the sales of copies are built into the decision about whether or not to update maps, do additional flyovers, and that sort of thing. I don't know about taxes in WV, but here in Mass local government is very very lean, and I can easily see someone in a similar fiscal dilemma deciding that the best way to pay for more frequent updating of mapping (which with flyovers and such is fairly pricey for a small town or county) is by generating revenue from the maps. Particularly as most of the users of mapping are businesses--this doesn't apply quite as much to tax maps, but our GIS layers are pretty expensive to produce and when 90% of your requests for GIS maps are from business who would otherwise need to do the survey work themselves, it's a fine line between public access and corporate welfare.
Also, having possibly out of date maps available in a central archive does kind of worry me. I'd rather have people getting them from us directly. Citizens have a habit of getting the wrong end of a stick on something and storming into town hall irate out of their minds over problems that don't really exist. I've had irate people in my office banging on the counter and screaming waving printouts of some web site somewhere they found that they thought was our official one. Part of managing a municipal website is trying to figure out ways in which information can be presented where citizens will not be confused and assume the worst and where it will be kept accurate and fresh.
Having said that, I agree with most of the people here. These are public records. All our GIS layers are on our website in addition to the ones that are on MassGIS, which includes a viewer. We're adding PDF'd tax maps as of our next update. Our property record cards are available online. I think and our town thinks these are records that should made as widely available as possible. But IMHO that's not the only legitimate way to look at things.