Well, he said, you can easily join the "$VENUE_guest" network. But it will require you to verify your phone number.
What? I asked, You mean it will send me a text message with a code?
What if I don't have a phone?
I suppose you can create a Google Voice number.
And look at it how, without access to the WiFi?
Um, go somewhere with free WiFi?
. . .
I think it's quite the privileged outlook that led someone to the assumption: anyone who might need the venue's WiFi will of course have a phone in their pocket.