They'll drink from it..not to worry. They are seeing something "strange" to them, they're not liking it one bit. What you need to do (if it were me) go sit out there and "click" the stainless steel thingie...keep clicking it and eventually they will come over out of curiosity. Once you get one to drink, they'll all drink.
Make SURE you have it at the right height so they don't have to stoop so much to get to them.