I'd imagine it would be seen as god's punishment to the lower classes. And as the nobles and clergy spent most of their time inside and are told to have been quite pale - and therefore didn't suffer from skin cancer as much - I'd assume it only contriuted more to the idea that god prefers the clergy and nobles over the serfs.
Before other responses come in, you might be interested in the previous answers to questions related to the protection from sunburn in the past, such as:
Sunburn and Roman remedies for it as described by Pliny were mentioned in this thread by u/RexSueciae
Medieval remedies for the sunburn, some of ancient origins, were explored in this thread by u/sunagainstgold.
Input concerning practices in ancient Egypt and medieval France can be found in this thread by u/waspocracy and u/grantimatter.
And last by not least, you might some information about actual relation between sun exposure, sunburn and skin cancer in my previous response to a similar question.