Infrastructure fees include dedicated servers, PCI DSS and maintenance, security monitoring, and the technical environment needed to process payment transactions. A shared environment is cheaper to operate — but it is not white label.
A provider using shared infrastructure cannot offer true white label isolation — and every provider using shared infrastructure is passing that limitation to the business.
Dedicated infrastructure per client is a prerequisite for true brand separation, compliance independence, and full routing control — a non-negotiable part of any genuine white label payment gateway.