I can see it from both points of view. I am in the process of purchasing a home here. My hubby and I are still in the mode where we get up in the morning and look in the rec news to see what is happening for the week and if it sounds interesting we show up. If, in the write up, it asks you to contact someone before showing up we do that.
However, we have shown up for a few activities where there were no people, or it was a closed group. It was disappointing, but I blame that more on the rec news putting in more clubs and activities than they actually have available. Perhaps they could ask all leaders once a season to send in an update to determine if a) they are open to new members b) they have limited availabilty for new members c) they are full right now, so take them off the list of possible things to do c) they are on hiatus for the summer, with next meeting starting in <put date here>.
They do seem pretty good at pointing out levels of each activity, so we don't show up for advanced when we've never done it before. And in most cases, folks are very welcoming to new people.