Peppermint shrimp eating out of my anemone??

As some of you know, I've been running my tank fallow for 5 weeks now because of an ich problem.  I've been lightly feeding the main tank to keep my shrimp, crabs and anemone happy.  Today I target fed my RBT anemone a large amount of mysis and saw my largest peppermint shrimp crawl INTO the anemone and grab mysis 2 or 3 times!  It was done by the time I got my camera downstairs, but I thought it was insane that the shrimp went in there and didn't get stung and eaten.  Maybe the shrimp exoskeleton protects it enough?  I'll try to get a video of it the next time I target feed the anemone, although this is the first time it happened in 5 weeks.

 

I Use tol get shrimp and crabs trying to steal food from my anemones all the time. Now I just feed them first and save the last for my RBTA.

 

i believe several types of shrimp are immune to an anemone sting.. maybe all are? Perhaps it is the exoskeleton that protects it. My old fire shrimp did that all the time.