Let's first admit that this movie is not some deep drama or social commentary. It may have a good message, but it isn't shoved down your throat. In the end it is just a fun movie to watch.
Having said that, this is one of my favorite movies because of that good message and, more importantly, because of the way in which it is presented. Countless movies and books have been centered on the basic theme of this movie - namely the intergenerational friction between teens and their parents. Unfortunately, most of them fall into the same trap and paint one (or both) sides as stereotypical in the extreme. Frequently this shows up by having kids that are ultra-clever battling against bumbling adults (Breakfast Club or Ferris Bueller's Day Off - both of which are enjoyable - come immediately to mind, but the list is oh so long). Usually, the kids have no apparent concrete reason to be battling the adults and the adults merely want to be obeyed because they are adults - they don't appear to have any desire to actually do what's best for the kids. In the end, these tales usually have the kids triumphing over the adults.
Footloose largely avoids this. At first, it appears that the adults in town are going to turn out to be cardboard cutouts transplanted from all the other movies in the genre, but it quickly turns out that the adults are not evil, nor stupid, nor uncaring. They are genuinely trying to do what they believe is best for their kids - and they realize that they aren't infallible and that they don't have all the answers. In the end they are willing to consider change not because they are convinced the changes are necessarily right, but because they respect and trust their kids.
For their part, the kids aren't rebelling just to rebel, nor are they trying to deny their parent's authority even as they struggle against it. Quite the opposite, they largely work within the bounds of the system their parents have set up in their quest to change it - and their parents. They do so because they respect and trust their parents. Furthermore, they are willing to accept defeat when it appears their best efforts didn't win the day.
What this film portrays so well is that parents and their children may have different outlooks and priorities and they may come into passionate conflict as a result - but they can do so while the mutual love, trust, and respect endures.