We leave the font out for a few days. People will dip their fingers in it and cross themselves when walking by, fill up containers and take it home, etc. Sometimes we will sit cups out (like the ones we use for the wine after taking communion and before taking the antidoron) and people will simply dip one in and drink from it. After a few days, the water is dumped into the ground.
I've never heard about baptismal water being treated differently from holy water. IIRC, the same blessing of the water in the baptismal service is the same blessing given to holy water at other times. I'm curious to hear more about this tradition, it's completely alien to me.
Our baptismal water usually has a good oil slick on it by the time everything is done. And hair. So, besides what else might be in it if babies are baptized, I would not drink the oily, hairy water. Sucking spilled communion out of dirty carpet is one thing, that is quite another.