It must be well-stated and understood that affiliates are all individual business persons with their own unique and peculiar characteristics. That is what defines how they do business and relate with other affiliates as well as their sponsors. To take on this matter directly therefore, YES there are certainly limits sponsors should not go beyond in their dealings with affiliates in this business relationship.
SFI clearly defines what sponsors should do and should not do in their “awesome sponsor” page found on this link: https://www.sfimg.com/Training/AwesomeSponsor. That clearly sets the limits for all affiliates and sponsors. Once you keep to the rules, sponsoring affiliates presents no special challenges thereafter.