or is it good manners to invite someone you know to join you if you are at a soft play place?

[deaconblue]

Took the dcs to a soft play place this morning. Was really busy so I sat down on the edge of someone else's table (obviously asked first if this was ok). Later on I noticed my friend's dd so I got up and looked for my friend. Was surprised when she said "I saw you walk up and down a couple of times" and then didn't invite me to join her and her friend. So I chatted for a couple of mins and went to sit back down on my own again.
This isn't a close friend, she's someone I see at a weekly coffee morning but there are only 4 of us who meet so it's not like we don't know each other. Thought it was really a bit rude and made me feel a bit crappy. If I saw someone I knew I would have called over and asked them if they wanted to join me.

I just thank God I don't have to go to soft play anymore

She probably thought you were with the people you were sharing the table with.

YANBU. I'm way beyond soft play but in any similar circumstance had I been at soft play, in a cafe, with a friend and if someone I knew came in on their own even if I didn't know them very well, I would invite them to join us. It would be an opportunity to make a new friend as well as being good manners - no way would I ignore someone I knew and give them the cold shoulder.