Agree, generally, and let's also be clear that at-home inflation comes not just from one judge from that home country, but several judges on the panel that are NOT from that country as well.
When it comes to the big markets like Russia/US/Canada, I would bet that the ISU considers it in their best interest to encourage the wins of skaters on home ice. The ISU needs to sell tickets, and it helps to sell tickets to future events if the home favorites seem likely to win. If you're a casual and you decide to pay money to go see skating, you're just going to root for whoever is from your country. If you see them win and get excited, you're more likely to be more invested in the sport and more likely to spend money on a future skating event.
The success of home skaters on home ice is a BIG DEAL with financial perks.