Really? Do you actually think they're equivalent?"
I didn't say they were equivalent. I said they were fun for the same reason. Once you get past the fact you're talking about death, it's just another guessing game. And the point IS to get over the fact that you are talking about death.
Nobody's really been able to explain what's so objectionable about it beyond a vague 'lack of respect' or 'poor taste'. It doesn't trivialise an event to discuss it on an intellectual level. There is no lack of consideration towards those emotionally affected when the discussion takes place purely amongst strangers. The fact that strangers are capable of discussing someone's death intellectually does not in any meaningful way devalue that person's life.
To be honest, I think underneath it partially stems from a lack of fatalism. I have this theory that we handle the subject of death so gingerly not because we can't control it, but more that we feel we do control it but we don't know how. So we feel a mass of pressure on the choices we make because the thought always lurks that it could possibly impact on the outcome. Even to the point of feeling guilty if we speak flippantly about the death of somebody who subsequently dies, lest we gave the universe ideas.
My favourite gods of classical history are the Three Fates. The first holds a distaff and spindle, and spins the thread of a person's life. The second carries a rod, and measures its span. And the third carries scissors, and determines the manner of their death.
According to Roman mythology, this all occurred on the day of your naming ceremony - a week or two after your birth. I find that mentality towards life oddly liberating.