How difficult? Is running 1000 minis worth $1,000,000/month of effort? I feel like it is.
Very smart play to build a platform, get scale, and prove out the software. Then either add a small network fee (this could be on money movement on/off platform), add a higher tier of service for money, and/or just use the proof points to go get access to capital and become an operator in your own pool.
This is essentially the same reason even the best money managers take outside money to start, even if they eventually kick out the investors.