I guess I'm just weird this way...
I keep an assortment of any kind of screw I may need, right in my driver case, in a zip-lock baggie. Any time I have an extra screw(s) left over from whatever I'm doing, I'll just add them to the ones in the bag.
Reason, is many times at work I'm doing something that requires just a couple screws, and many types will work, but I don't want to go hunting for them, so I usually have something that will do the job, right in that plastic baggie.
But what I
won't do, is use screws with different heads, if there's a good chance someone
else will likely be the one who ends up removing it later one, as in something temporary.
Cuz I can't stand removing 3 screws of one type, then having to dig out a different tip to remove the last one!
I guess it's not only in construction, in which people never think about the person who comes behind them.