Watching and being watched can be exciting with the right people.
I have done both... in clubs and privately with couples.
In fact, my first experience with a couple happened to me spontaneously in NY. I was in a jazz club. A couple sitting next to me started chatting with me. They were fun, friendly, and nice. The wife was a lil flirty. Eventually, she went the bathroom. Her husband then said something to the effect, "I think she likes you, would you like to go back to our hotel with us?" I was kind of shocked, flattered and surprised all at once. So I went we got stopped at a store grabbed some drinks and went back to their hotel. Things got heated quickly... and the husband ended up watching me pleasure his wife.
I had something like that happen again in NYC. Both times were so random... but I have learned to read couples now. You can kind of tell which ones like to have fun.
But so glad the first couple gave me such a nice experience. Now, I like it.