There have always been boundaries, and fairly generous ones at that, which permit a wide variety of behaviors, but draw the line in some vague place. So you would draw no line at all? If the kiss was fun, why not just jump into 69 right in the bleachers? Then would you oust them? I could keep coming up with progressive examples, and eventually everyone would reach their point of saying "stop", some sooner than others. People that intentionally find boundaries shouldn't be surprised or upset about it, that's what they wanted, right?
See, now your just getting ridiculous, Tom. I never advocated pictures in the stands (though, that might be better than some of the Nats games going on right now.)
Being in a crowd of 20,000 is pretty damn public no matter how you spin it. Where are you then? Your certainly not on/in your own private, personal, residence.
As for the argument that they "violate privacy" that is total bullcrap that not even a cow would admit to dropping. Okay, pretend it is. So those lesbians violated your privacy. Yet, your violating their right to the pursuit of happiness. There really is no way around this, it just goes in circles. It all boils down to one thing this country just isn't good at:
Tolerance.