The "public kiss" signified more than it might seem on the surface.
This was an example of Blubberhead's defiance. She has, undoubtedly been told not to kiss in public. It would draw unwanted attention, perhaps even authorities, and they would be scrutinized. Salah probably told her ixnay on the isskay. As a low status refugee, he does not need any extra attention cast in his direction.
El Stupido, however, believes all rules must be broken. So, thinking she was so clever, she devised the hand-kissing stunt to circumnavigate the rule. Just in case nobody got it, she announces "public kiss" in a taunting, singsong voice. Catch me if you can, she almost seems to be saying. Very cute and quirky, if it didn't run the risk of getting them beaten, imprisoned, or killed. She doesn't believe that could happen though; she has learned through life that actions never have consequences, and that breaking rules has let her enjoy a taxfee, reckless life with impunity.
Salah is a moron (not as dumb as Roman, though), but he isn't a retard. He knows that little ham kiss was testing the edge, and he also knows that in the wrong hands, it might be seen as offensive. Probably nothing would happen, but it is better to be safe than sorry. So he told his sassy, rule-breaker oaf of a girlfriend to delete it. Of course, the dumb fathead bungled it, so that only the kiss was uploaded, which is even worse and more provocative than it being ten seconds of an innocent, ten minute video. Thanks a lot, tubby.
Salah had better watch out. Her defiance of all authority remains a core part of who and what she is. She can't help herself; rules make her bristle, so she's gonna be testing the edges of them some more, growing more emboldened every time she gets away with a little more.
There are women in this world that men need to steer clear of. They are the ones who sass cops, encourage fights, create scenes in public. Even if she is hot, a wise man knows enough to stay away from her, because she can and will get you into profound trouble with her big fucking mouth. Chantal is one of those, and doesn't even have the mitigating factor of being hot.
Public shows of affection are very important to her. Not because her heart is full of love, but because she can show it to the haters and tell them to eat their hearts out. She will push the issue again, probably at a very inappropriate moment or in an inappropriate place. Salah will get the brunt of the blowback, if there is any.
This story will not end without Salah regretting bringing her there, in one way or another.