Are your concerns specific to NinjaTrader or a general question regarding all platforms that offer the ability to develop your own systems (AmiBroker, Multi-Charts, etc, etc)?
In my experience, NT seems to be a pretty good front end (charting, etc).
The same argument might be raised about brokers "riding your coat-tails." In all honesty, they have an easier time of determining who is making cash than NT does since they actually have access to your accounts.
In any event, if you are really concerned about the 3rd party platforms "snooping" your actual trades/core logic, there are ways around that. It's not actually rocket science, and if you are familiar with c#/Windows you've probably already arrived at that conclusion yourself.
In my experience, NT seems to be a pretty good front end (charting, etc).
The same argument might be raised about brokers "riding your coat-tails." In all honesty, they have an easier time of determining who is making cash than NT does since they actually have access to your accounts.
In any event, if you are really concerned about the 3rd party platforms "snooping" your actual trades/core logic, there are ways around that. It's not actually rocket science, and if you are familiar with c#/Windows you've probably already arrived at that conclusion yourself.