You can choose to set different prices for add-on fields depending on the user role.
Just go to WooCommerce > Settings > Product Add-Ons and enter the roles that should have different prices set in the ‘Role-based Pricing’ field:
This will add an extra price field for each specified role for every add-on:
This means that the standard price of ‘5’ will be displayed for all users except users with the role of ‘Wholesale Buyer’. For users with this role, the price will be ‘4’.