Where I live, it's not an issue in the fall. But we still have winter and I wear tights when it's cold. No problem wearing them on a bike.
On days when it's too cold for biking, I wear them under my pants on the golf course. Especially on cold and windy days. But in this climate there are days when it starts out in the 30s and then rises considerably by afternoon. The whole ensemble can get a bit warm then and I've fleetingly considered just taking off my pants. Women in their 20s and 30s play golf in tights. But I fear that's a step too far. I think a 60 something guy on a bike with tights is fine, but on the golf course it may cross one of those unwritten social codes.