Generally speaking you can use the mobile website and add the QR based boarding pass to Google Wallet that way - but if you dig into the TOS you'll almost certainly find an alternative way to get a printed pass.
For example Ryanair, who went 'fully digital' last year and stopped accepting self-printed passes, will provide a free of charge boarding pass at the airport so long as you have already checked-in online before arriving at the airport.
I mean they're the discount bus of the skies, designed for students and people on weekend breaks inter-EU. Avoid flying to Paris (Buvais) or certain other 'city' airports, keep your carry-on luggage within limits, and they're basically fine.
They've a safety record that's beyond reproach, and where else are you going to get flights for ~€50 across Europe?
If nothing else they disrupted a predatory pricing cartel. I'm old enough to remember when a flight England->Ireland or Spain->Portugal could be the guts of €300 or €400. Now we have a complete revision on pricing and it paved the way for multiple good budget carriers like Transavia.
Not to mention Michael O'Leary being an absolute rogue with his PR - particularly the recent spat with Elon Musk
For example Ryanair, who went 'fully digital' last year and stopped accepting self-printed passes, will provide a free of charge boarding pass at the airport so long as you have already checked-in online before arriving at the airport.