What is it with you and many others who have to be derogatory about pubs and bars when it is not needed?
My pub welcomes responsible dog owners and is observing social distancing measures. We do not need people adopting an Orwellian view of people who don’t go to pubs are good and those who do are ‘ballsacks’.
On topic, an ethical way to get a dog is through a local dog’s trust charity. We’ve had our previous two dogs through this method and it has been very rewarding. Our present fella came with, what to all extents was, a doggy ASBO! We we’re told he would always be a nightmare and not able to mix with other people or dogs. After a couple of hard months - and many,many hours work - he is perfect with people and tolerant of other dogs. His character has come out and is the most affectionate pet we’ve ever had. Well worth all the effort - but be aware whatever the dog , a lot of time and effort will be required.
In conclusion to the OP, if you have the time and willpower, go for it. The fact you are asking about ethics suggests that you’ll be a good fit. When you get your pet, go and enjoy some lovely long walks - then treat your mutt to a bag of pork scratchings and treat yourself to a pint of ale in one of this country’s greatest institutions - the pub