I doubt they could ever be profitable just by retrofitting machines with a one-time sub-$10 part - they need recurring revenue streams from an installed base
This is not correct. Eports have a one time install/sale profit and monthly reoccuring revenue because when an Eport is installed it must be also hooked up to USALive, USAT's credit card processing and machine monitoring system. The real idea is to get enough macines on USALive to gennerate positive revenue from monthly service fees.