[tvst]

Or perhaps the opposite could happen: as more and more people start carrying devices that have access to the internet via cellular connection, airports could start providing Wi-Fi for free, as they could use that for tracking, marketing, and other "fun" uses

[Macha]

I think it's roaming fees that really get airports able to charge for wifi. 4G on my phone is already way more reliable than any airport wifi, and since within the EU it doesn't cost anything to use my data allowance while roaming, I never use airport wifi in the EU, it's only in the US I use it because there I have to pay €10/gb in advance for roaming data allowances.

[dzhiurgis]

Get Google Fi via eSIM before you leave. I haven't tried, but seems possible.

Wonder why there isn't more companies doing same minus Google weird UX and creepy tracking.

[Mary-Jane]

Google FI user. I can confirm it fantastic great for international travel.

[rhino369]

ORD and DCA have free wifi and they collect emails presumably for that marketing purpose.