Ok, so I should update this.
I searched around a bit and figured that the only valid concern was that the chicks might eat too much of the bedding and get impacted crops. However there were also reports of compacted crops in cases where the chicks had eaten pine shavings or other bedding types.
So I eventually just went ahead and used the sand. The chicks browsed it a little but didn't eat it too much and thrived well on it. Lived just fine on it for 2 whole months.
Here is a pic from mid December last year, after they had been in the sand for a month:
I sifted the sand with a tea strainer every couple of days. Eventually it had to be replaced as the moisture built up, and I replaced it 3-4 times in total, once because of spilled water.
The only real concern in my experience after this trial is that the used sand has to be thrown away and can not be composted. So in future I might try to use some other organic bedding.