I can understand that clearing up after your pet can be an unpleasant experience, but that is no excuse for ignoring the fact that YOU are making it an unpleasant experience for everyone else who happens upon the mess you leave behind. Surely when you pass there again with your dog you must see what you did, know what you did, and have to avoid stepping in it yourself. You look around whilst your dog squats down to do it again, either because you're embarrassed, want to be ignorant of the fact that your dog is fouling the pavement, park, gardens, play areas, so that you can plead innocence if approached by someone, or you are merely looking around to see that nobody is coming so that you can walk away before getting out a bag to remove it.
Perhaps you do not step in any, never have to scrape it off the wheel of your child's pushchair or bicycle, you've never had a job which involves using a lawn mower or strimmer in public places. Maybe you don't mind that on hot days there are places that stink of turd so bad it makes you gag or that your child is playing in it whilst you're having a picnic.
You are probably also not aware of the amount of toddlers that contract toxocariasis, a disease that causes serious eye damage. Certainly there is no sure way to prove that YOUR dog shite caused this in anyone, but how can you be sure that it hasn't or won't in the future?
There are NO valid excuses for not clearing up after your dog. So do not try to come up with any. We have heard them all before and none of them are valid. There are many many more reasons why you should be clearing up your dog mess and disposing of it responsibly, not only for health and hygiene, moral and legal reasons.
Should you be fined? YES
Should people have the right to ask you to clear it up? YES
Do you have the right to verbally abuse anyone that asks you to clear up? NO
Are you flouting the law by not cleaning up after your dog? YES
Name and shame
I for one will be taking photos or video before during and after any such activity, and send it to the appropriate authority. These will also appear online in the hope of naming and shaming you into acting responsibly, although I suspect it won't but that won't stop me from trying.
I would also advocate fines for any dog owner NOT able to prove they are worming their dog(s) regularly or having with them at all times (when out) at least one bag or a poop scoop.
I recently saw two elderly people whose dog left a runny mess on the pavement, it must have been ill, they had nothing with them to clean it up. Had I not been walking past perhaps they'd have hurried along but instead they fumbled around in pockets, pulling out handkerchiefs and realising they weren't adequate enough. Passing by later I saw that it had been partly scraped away and covered with leaves.
For those of you who still think I am barking up the wrong tree here's some researched information provided by Keep Britain Tidy.