I Don't Understand. . .
Albert Goshman used to waddle over to a table, smile and ask, "May I Magish for you?" and thus moved into his bit.
My two "openers" if you would went like this. . .
First Scenario: Walking up to a table and looking around as if I lost something. Reaching the target table I bend down and look under the table cloth and say, "Ah ha, there you are!" I'd then stand up, apologize for interrupting the guest. . ."I'm sorry, but as the house magician I have a terrible habit of leaving my props here and there. . . usually stuck under a table because of all the chewing gum. . ." at which point I reach under the table and on cue. . . "in this case I'm quite surprised you didn't notice it (I bring a small 8" Bird Cage from beneath their table), it's not exactly a little thing. . . it's ok, you can pet my bird. . . his name is Chomper. . . . Chomper is one of my special assistants in that he is one of the fastest moving canaries on the planet. . .
". . . I see you don't believe me, sir. Well, allow me to demonstrate. . . " and so, bird & cage vanish in an instant, everyone at the table gasps in shock and for some odd reason, expect me to do a bit more to startle and amaze them.
Yes, this is the exact same type of Bird Cage both Blackstone's made famous and yes, you can safely do it close-up if you practice the handling of it. However, this approach isn't mine; memory serving me correctly it was Channing Pollock that originally used this approach back in the 1950's.
Second Scenario: As with the above I am looking for something and finally look up at the guests sitting at my target table holding my left hand in a manner that has the first & second fingers together at the "top" and my thumb below in a "C" shape, indicating empty space where something should be. . . "Pardon. . . have you seen any of these laying around?"
Of course they haven't, so I feign embarrassment, "Oh! Let me dust it off so you can see it better..." and voila! A nice bouncy sponge ball appears from nowhere! Needless to say, I'd then move into my sponge ball routine from that point.
Either of these routines are invasive; that's to say that I simply walk straight up, interrupt what they are doing or discussing, and simply start doing magic. It's not until the first phase of things is completed that the guests are given an opportunity to accept or reject the gesture/ an offer for some amusement. While I can fully understand why some wouldn't like this approach (I know that it can seem a bit invasive and even rude at times, which is why you must "read" the table before approaching it), it is one of the best methods I know of, for convincing grown-ups that it's ok to enjoy a bit of mature magical entertainment (you'd be amazed as to the number of people that shun the idea of watching magic tricks at their table in that "tricks are for kids"... right?)
There are other approaches for "opening the door" so to speak. I think it was Johnny Thompson that would ask people if they wanted to see the worlds best, most dynamite card trick. . . it doesn't matter what card bit you do in follow-up, just CONvince them of the fact and from there move into your shtick. Another approach (though not all that popular for varying reasons) is the "Magic Menu" approach; as the name implies, you have a menu that describes certain routines you do and guests literally order their entertainment as they order their meal. In the original version of this approach there were literally prices set on these routines; instead of the facility paying you or you hustling for tips (which is not wise) you charge them up-front. Needless to say, it was not a successful concept even though the general idea of a menu is of value. Not only can you use it as a way to get-in on a table, you can likewise use it (or the house menu) as part of your routine . . . as a book test, PK effect, (if it's paper) a torn & restored, etc.
Actual "starter pieces" to your close-up don't have to be over the top and in all truth, don't have to be a "feature" segment. Using pieces as a lure, such as I note in the above, is always solid thinking. On the other and, allowing a loop to snag the tong of a fork as you introduce yourself to folks and then causing the fork to move. . . well, you again give them a "taste" but this time it is without the feeling of being "invaded" or "imposed upon". BTW... if you do the fork thing or something similar, you still win in that they will talk about it . . . so be creative/ resourceful, practice various bits that can be done quick & clean that gets peoples attention. The rest is just your personality.
its okay to have a favorite category of magic. But you have to have variety as well.
