I posted the IDNR link earlier. What gets me in IL, is that most state parks here are CLOSED ANYWAY until mid-April or later. I mean, some you can drive thru, go hiking, but no camping until mid-April or later. So I tend to agree closing them makes no sense as attendance is low now anyway. And for us, a weekend or long weekend (memorial day / labor day) of camping, we just use our own equipment and not the pit toilets/showers/etc.
From my own personal perspective, it hurts that we moved from a perfectly good TT to a new Class C last year, and my girls went to Space Camp in Huntsville AL where we camped that week with them. That was it. 1st and only usage. This year, we have 2 weeks planned for Colorado, in addition to local IL state parks. I get the feeling my usage may be low again. I hope not, but I'm bracing for it. At least it's only camping reservations (made in Jan for Cheyenne Mtn SP) and not airline tix / etc.