Now that you have all done your government bashing, the reason for the notice is a release from liability. You have been informed of the issue and if you choose to use your RV or trailer you are doing so at your own risk. This gets Dometic off the hook for any additional damage caused because you decided to use your RV despite knowing of this issue. The NHTSA is also advising you not demanding that you not use your RV until the awning is repaired. This is still a free choice country and you can still do any stupid thing you want to.
Randy
p.s.
Sometimes a manufacturer will instigate the request for a recall to limit their liability for additional damage.