sometimes you can get away with putting stickers under the drive thru windows at restaurants while you wait for them to get your food (most probably have cameras). Another place i've seen a lot of stickers is on those traffic signs on poles that stick up out of medians while you're at a light waiting to turn left. You could stick some to the foldy seat part on the shopping carts where you put your kids. Also as the weather warms up more people will be out hiking etc. you can go along trails and stick them on signs or trail markers (they're not frequently monitored).