So, back to the original question, I am paid by the hour, so mileage does not apply. I'm paid for every minute I'm doing something related to my job. It's not seasonal, it's predictable and steady.
I will not say people who work for mileage are chumps or people who work for percentage are any better or worse than anybody else. It all depends on your specific contract and needs. If your needs are being met, your treatment is acceptable and you like what you're doing, it doesn't matter who tries to knock you for your choices.
One guy might make $100K/year gross but rent a house in urban California while another guy makes $60K/year and owns five acres in rural Idaho. At the end of the year, the guy in Idaho will be further ahead simply because of cost of living differences. So saying, "I make this and if you don't also make this, you're a chump." is not very smart when the bigger picture comes in focus.