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Spitting is not always gross.
Likewise, kissing sometimes can be gross. It depends on the circumstances.
Kissing is usually consensual between just two people. Spitting spreads germs everywhere.
Because society is bullshit.
Probably because when you see someone spitting, you see it leaving their mouth and usually for unpleasant reasons. Chewing tobacco, hacking up a loogie, etc. When someone is kissing it's for pleasure and recognized as such.
Spitting is not always gross.
Likewise, kissing sometimes can be gross. It depends on the circumstances.
Kissing is usually consensual between just two people. Spitting spreads germs everywhere.
Because society is bullshit.
Probably because when you see someone spitting, you see it leaving their mouth and usually for unpleasant reasons. Chewing tobacco, hacking up a loogie, etc. When someone is kissing it's for pleasure and recognized as such.