Is this bad etiquette from a dog owner? His dog pooping on my front lawn

So, to help understand how this happened, it's worth mentioning I'm from the UK and in our neighbourhood the public pavements (walking paths) are right next to the front lawns and driveways of the houses.

So it's very normal to have dog-walkers passing by and their dogs having a sniff or two around the edges of peoples front lawns/driveways

However this morning (on my camera I saw this) a dog owner was casually walking his dog on a lead and watched him walk on to our lawn (a couple of feet in) and allow him to do his business. After watching him and letting him finish, he did go over and collect with his poop bag.

But my question(s) is:

• Is this bad etiquette on his part – to allow him to poop there in the first place?
• Or is it a case that, once a dog has decided where he's to poop, you cannot (or should not), disturb him from doing so. And therefore can only make a move once he's finished?

Personally I found it alarming/disrespectful. But I'm wondering whether that's just me not being aware that, in fact, it's very normal?

**EDIT – I forgot to mention on our public pathways there are grass verges and plants / trees where, normally, dog owners allow them to do their business