If only we all wanted to be treated the same way…
Count me among those who absolutely do not want strangers sharing my table. I would never ask someone to join them at their table, and I would rather no one ask me to join mine. I’m a hardcore introvert and while I am eating, I need my bubble of space to “introvert”, at least as much of a bubble of space as one can get at WDW. I am generally traveling in only a group of 2, so we are often sitting at a 4-person table because that’s mostly what is available. I don’t mind if people ask to take a chair, but please don’t sit next to me.
That being said, I fully understand that there are many people who feel exactly the opposite of me, maybe even most people, so I keep my counter service dining at WDW to a minimum and when I do eat counter service try to go at off-peak times to avoid the situation all together and stick to table service at restaurants without shared tables. No Teppan Edo or Biergarten or Sci Fi unless traveling in a big enough party to fill up a table ourselves.