So one trick I learned in my LFS days was certain anemones (and only certain ones) you could basically "let them know you were there," massage their bases and get them to let go then scoop them up. I vaguely remember being told to stick with condys, LTs, and maybe sebae's(?) with this trick b/c you would get zapped by most others. We typically used this method to bag them up b/c it seemed to be the quickest and least stressful method to capture.
However, the only other thing we routinely had were typically carpets and there were arms in the tanks constantly so maybe they weren't bothered by it? This was 15+ years ago though so I am sure not a common practice anymore.
****Fair warning this might end up in the worst advice ever given thread so if this is horrible advice someone please jump in!!!!****