Ok I'll bite. Blocking the whole aisle at the grocery store shouldn’t be something that's looked down on. The person rudely interrupting my conversation should be more looked down on. The reason is that having a conversation doesn't intrinsically interfere with anyone else, but interrupting us and walking in front of us absolutely does.

All shoppers have the same and equal freedom to have a conversation if they choose, except for the people without friends of course. If that interferes with the shopping of the person trying to get by me that's not my problem. The designers of the grocery stores should ensure that the aisles are wider so they can get by me. The grocery store constructed this scenario all by themselves and if there's a problem with it they should solve it themselves. I shouldn't be asked to sacrifice my conversation when I’m buying groceries (just like everyone else) because they failed to do that.

If we're really insistent that this is somehow not 100% the grocery store’s problem, I'd next argue that if you don't have enough room to get by in a regular row, then you're literally too big for that store. You should go fuck yourself. The grocery should force you to do so.