Please post a screenshot of what you are seeing when you are trying to order. Maybe there is some option we are not aware of in Europe for tesla (although I doubt it).
Whats much more likely to be happening here, is you are ordering (or leasing) through someone other than tesla, and they are adding some option onto the car like car dealers do for seat treatments (like dealer installed scotchguard or something).
Tesla itself does not offer anything like that we are aware of, but if you are leasing the car through some third party company, they may be offering you something that is likely not necessary. Teslas model 3 only has white and black seats, with no "treatments" or "pur options" on them from tesla.