Our local secondary school had an appalling reputation, but has worked hard to improve this over recent years. It now gets much better results, has a smart new uniform and the children somehow seem much more lively and articulate when seen out in town.
The school have put up a banner advertising "Use our new fitness suite for free on Saturday mornings"
Now, "for free" doesn't sound right to me, but I'm not exactly sure why. Before I point it out to the school (because I hate to see them spoil their new improved reputation) am I right?