"Why do all these dog walkers have flower-scented bags for dog poop? I never see these bags in the pet stores."
that's not venting. You're not upset with the dog walkers for having flower-scented bags. You're not complaining that they should not have them. You're making an observation about something unusual.
To me it'd be like saying
"that Ferengi drink holder has a clockwise spiral design in it, so the liquid spirals clockwise as it comes down towards your mouth. Do you think if they had them in Australia that they'd have to use counter-clockwise spirals to get it to work right?"