They survive by selling a lot of overpriced and unnecessary protective filters to newbies.
It's why there is such pushback when you say these filters are not necessary.
They do like to push unnecessary filters, precisely because they have a good margin. But realistically they offer plenty of other services. You and I might not be interested, but other folks are. They can scan old photos, transfer old videos, do custom printing, clean sensors, etc.
To sidestep the push back don’t argue the point, just say no. Arguing the point just invites pushback because they figure you might be persuaded.
Another thing they can do is save you the trouble of selling your old gear by taking it in trade for a credit against new gear.