It is generally preferable for all people to have the same contracts within a franchise network. It makes it easier for franchisors to manage their networks and franchisees feel fairly treated.
However, this is not always the case because franchise networks are built up slowly and the matters of concern are often totally different to those when the franchise began. As a result, it is possible for there to be different contracts within the same franchise networks but this is not a legal problem.
Regarding the more specific question of fees and payments in general, entry fees often differ within a franchise as they correspond to different situations. The entry fee that has to be paid when a network has 100 sales outlets will not be the same as when it has 200 or 300 because the larger a network is, the stronger it is and so the more advantages it offers new franchisees. The entry fee may, therefore, be higher for those joining later. Full article.