You checked the price of any petroleum or plastics-related product lately ? You're not in 2019 anymore.
And yes I know it usually costs (way) more than $10...but for that you get a nice holder....certification and grade....listed in the registry/archives for that TPG.....etc.
You have quality professionals (some of whom are on these forums) spending their valuable time on your coin. They're not a charity, they have to earn a living.
Maybe on a lower-priced coin the $$$ are a nuisance to you. For myself, usually buying nice silver or gold coins ranging from $150 - $2,500.....I'm happy to pay an extra $30-$50 or whatever it costs for the convenience, protection, and grade on the holder. Light-years better than having a raw coin in a velvet pouch.