Is it ok to give videographer/photographer . . .

pics of people you DO NOT want in pics or video?

My little sister (26) and her boyfriend of 5 months DO NOT know the meaning of discretion. They are ALLL over each other ALLL the time! It is really disgusting and makes many people uncomfortable. He keeps his hands in her back pockets, etc.

So, I have great concern that i will have a handful of proofs of them and that my video will be of them -- they really make quite a spectacle. They are not engaged or married and i do not want my pictures (which are costing a pretty penny!) wasted on the two gropers in the corner -- or more likely -- smack in the middle of the dance floor. Can I give the photographer and videographer pictures of them and advise I do not want couples pictures of them, etc. For my older sistser's wedding my younger sister and her LAST boyfriend were ALL over each other and I do not want another random guy all over MY pictures. Should I speak to her? Should I try to tell my mom to advise them to 'cool it' for the night?

How would you guys handle this? Did you give pics or special instructions to photographer and videographer. It is particularly annoying at your wedding when you are supposed to look like the happiest most in love couple and there is your sister making out with someone on the dance floor (for those who have read any of my prior posts, my little sister is the one that is now on a starvation diet and a hard core gym regimen so that she can look better than me at the wedding)
HELP!!!