I am not worried. CET has cut so many other things over recent years that fiddling with reward credits would be their death knell.
I have about $750 worth of RCs and my husband has close to $1000. We use them for dining in Vegas, usually nothing else.
The downside is that there will never be any other comps while we maintain those credits. I don't think we are big enough fish to CET for amazing comps. We are happy with the free rooms, occasional free play, etc. in Vegas.
Joy